Space Solar Power: Star Player on the Bench

This is a guest post by Darel Preble, Chair of the Space Solar Power Workshop.

Our economy and wealth is constrained by the price of energy and our efficiency in using that energy to create value. Peaking fossil fuel production and climate change concerns have resulted in growing interest and subsidy for many forms of alternate energy. The EIA’s Annual Energy Outlook notes that no alternate energy is expected to take up the slack expected as fossil fuel production swoons over the decades ahead - the U.S. is doing NOTHING on the massive energy scale required. Among the contenders, the cleanest, most promising, most poorly understood, most daunting and most ignored is Space Solar Power. Why?

Integrated Symmetric Concentrator (- a NASA design circa 2001)

SSP is a simple idea. As the picture shows, huge amounts of sunlight would be gathered in high, GeoSynchronous Orbit; reflected by mirrors to photovoltaic sheets; converted to electric power; then beamed from a large transmitter to even larger antennas (rectennas - rectifying antennas - is the proper term) on Earth. Each rectenna is actually part of the grid of a contracting electric utility which would buy, transmit and distribute the power to their customers. Numerous competing technologies, many quite mature, offer robustness to SSP designs. There are numerous advantages to putting these panels in space, beginning with the fact that panels would collect 9.6 times as much energy per day at GSO than on earth, on average.

Since PG&E contracted with Solaren last week for the First Space Solar Power Delivery in 2016, controversy about this unique capability has taken on new life. Half a dozen other companies are actively courting SSP contracts, such as Heliosat, Space Energy, Space Island Group, Powersat and the Welsom Space Consortium. The reactions to Solaren’s contract are frequently dubious. Clearly Solaren and other SSP hopefuls assume their designs will win the Billions in contracts necessary to turn SSP into a winner. The joker in this big poker game is that you don't know the depth of money that may be behind a given company. And this game has just begun.

Any company starting to build an SSP System (SSPS) will incur significant losses for years before turning a profit. Google did that as people wondered about their business plan for years - they have established quite a fine business. Still, there is nothing else quite on the scale of the SSP challenge and opportunity - capturing the energy of the sun. An SSPS with reasonable assumptions about shading, collection and beaming efficiency, etc., could collect 3000 Terawatts at GSO and inject 1500 Terawatts to contracting power grids owned by participating utilities, such as PG&E, virtually anywhere on Earth.

As I have participated in several volunteer SSP studies including the NSSO Business Case Analysis and the Space Solar Power Workshop, I encourage you to examine this energy option more closely. Modern SSPS designs have many advantages. Here are the top ten:

1. SSP is “baseload” power available 98% of the year from GeoSynchronous Orbit. Energy storage, the Achilles heel of wind power and ground solar is not really needed, since the outages occur at local midnight during the equinoxes - minimum power conditions. A photovoltaic (PV) panel at GSO would collect 9.6 times as much power per day as the same panel at an average U.S. ground location. (See this PDF). Considering storage and conversion losses, a ground PV or wind installation would need to collect another factor of about 9.6 to store power for just tomorrow – assuming we only need to cover one cloudy day – not two or more.

2. SPS requires no fuel – zero pollution – and has no operations personnel. It is an antenna with green farms or ranches beneath the rectenna. SSP is the cleanest source of virtually unlimited baseload energy. Ground solar takes 100 times as much land usage to provide the same power as baseload SSP, similar to baseload power plants. Eventually Sunsat Corp could even provide much of its own fuel, through electromagnetic launch which even now has been developed as a first stage.

3. SSP takes advantage of our historic investment in aerospace and other technical expertise to increase STEM jobs. SSP technology is near-term-available with multiple attractive approaches and would create millions of inspiring and important jobs. SSP would revitalize America by taking advantage of a multitude of space-development-related technologies that are vitally relevant to our current problems, including

space transportation
control systems
aerospace engineering
wireless power transfer
environmental science including “space weather” knowledge

4. Unlike oil, gas, ethanol, bio-fuel, and coal, SSP emits no CO2 - it is a rectenna. Rising CO2 drives climate change, compounding our massive environmental problems with slowly declining global nutrition, since most plants, such as rice and wheat, are critically dependent on CO2 levels, and each plant, with its pests, responds differently. Weather changes from drought to hurricanes, we are still struggling to properly model.

5. Today's average coal-fired power plant withdraws 25,000 gallons of river water to provide an average household with 1,000 kilowatt-hours a month; 31,000 gallons if nuclear-fired. Waste heat is one of many problems with such baseload power plants. In drought conditions--a growing problem from California to the Carolinas--warming water from power plant exhaust has reduced power or shut down some power plants. Output water must be carefully monitored, especially in summer, to avoid fish kills from dangerously higher water temperatures. SSP cuts waste heat by about 80% and water use by 100%.

6. SSP would reduce competition for many other scarce resources besides water. Advanced thin-film space photovoltaic material now can generate 16.8 Kw/kg – using just one hundredth as much material as ground-type PV panels.

7. Unlike bio-ethanol or bio-diesel, SSP does not compete for increasingly valuable natural-gas-derived fertilizer. Corn can continue to be a major export instead of a fuel to burn, while raising the prices of foods from milk and eggs to cheese, hamburgers and Jack Daniels.

8. Liquid fuels can be made from SSP power, such as anhydrous ammonia which can be moved through the same pipelines as gasoline. It is 111 octane. We have been making liquid ammonia for 50 years for farming. It fueled the X-15 rocket plane! It can use existing piping, unlike ethanol. Synthetic fuels, electric hybrid vehicles and the electrification of our transportation system are all natural extensions of SSP’s beneficial impact.

9. Many other space businesses and jobs would be enabled by SSP’s low launch costs - from space mining to new telescopes which are now being considered for the Moon’s far side. Just as the railroad helped settle and open the western US, SSP can even provide a ready market for products made on the Moon or in space, enabling prospects such as lunar settlement, which this nation and others are committed to build and develop. Yet such settlements will not long endure if they cannot provide useful trade products, just more flags and footprints. SSP should have NO financial entanglements with these tangential developments, important as some may consider them, other than possibly being a customer on a level playing field with competing products from Earth. (It is twenty times more energy efficient to ship a product to GSO from the Moon than from Earth, for example.)

10. Asteroid protection is becoming more vital to not only protect Earth, but also a large assortment of critical space satellite resources. These are already subject to a growing panoply of threats from both hostile and natural objects. The advent of SSP increases the relevance and urgency of this issue, protecting us from a growing threat, as Russell Schweickart’s B612 Foundation have detailed.

** ~~ **

Closing the SSP business case depends on lowering the cost to orbit by an order of magnitude below the lowest costs currently available. The only market with the massive flight volume necessary to create such a market is however, SSP. This chicken and egg situation could best be solved by chartering a Sunsat Corp with the deep pockets necessary to bridge this chasm. Do not be distracted by claims that SSP requires “unobtainium”, such as space elevators, which are not on today’s horizon of feasibility. Advanced Reusable Launch Vehicles are fully capable of achieving such lower launch cost with SSP’s massive market. These could be obtained from many eager providers.

The time frame we have to address our energy and environment situation is rapidly dwindling. Historically, faced with such massive and immediate challenges in the past, the U.S. has chartered a public/private company to assume the job - from the Transcontinental Railroad and Telegraph (1862- Civil War) to Comsat (1962 - Cold War). There are simply too many engineering, financial, regulatory and managerial risks for existing companies to overcome, though many have tried since this new century began. Just as Comsat was chartered by Congress to build communications satellites, Congress should charter a company to build power satellites. The SSPW calls this new public/private company Sunsat Corp. Sample draft legislation, modeled after Comsat Corp, is on the SSPW website. You could buy stock in Sunsat. AT&T owned 29% of Comsat stock and assumed control. It would ultimately be a private company like any other international corporation, though regulated as a utility and also space law.

Some key principles in cutting the cost to build an SSP system are:

1. Cut the cost of launch to orbit. A major key to this is vehicle reusability - Spacex chief Elon Musk is aiming to build the first reusable launch vehicle, the Falcon 9, including a flyback stage. It would launch in under 60 minutes from the moment they leave their hangers. The path to lower costs is through higher volume – not bigger rockets:

2. Cut the weight of what you need to put in orbit, such as by using higher performance PV. As mentioned above, advanced thin-film space photovoltaic material now can generate 16.8 Kw/kg. That same film can be used on earth although it would be encased in a heavy protective panel to keep hail, sand, rain, pigeon “calling cards”, etc., out

3. Another way cut weight is to use control moment gyroscopes (CMG)s as the ISS uses for station keeping and ultimately to fly these “solar sails” like Clipper ships in the solar wind. Astro Aerospace Corp. built a 58 foot long by 10 foot wide solar sail that was attached to the north side of NOAA's GOES-8 weather satellite, and used to stabilize it against solar radiation pressure, saving station keeping fuel.

4.Don’t use astronauts to bolt the SSP together – use telerobots –they are 1000 times cheaper than using people in space.

Rectennas would actually be owned by local utilities. They best serve and connect to the gigawatts of customer load envisioned. Microwave wireless power transfer (WPT) is dictated by the equations to be naturally large scale. The efficiency of power transfer is determined by the diameters of the transmitting antenna and the rectenna - bigger is better. A rectenna will therefore be kilometers across, built in consultation with Sunsat’s marketing and a rectenna owner/operators group, SPARCO. Sunsat Corp would be a multinational super-utility, similar to existing multinationals in other industries, such as Intelsat. Incidentally, the safety of millions of microwave devices has been investigated by billions of people - as we use our cell phones against our ears, for example, and has been found to be quite safe. You could visit the giant Arecibo radio antenna in Puerto Rico and see a sample of what a rectenna might resemble. A lush jungle grows under Arecibo.

A typical draft ten year budget for this new public/private company Sunsat Corp, which the Space Solar Power Workshop has been constructing, illustrates how such a company could transition from the current dynamic market conditions to profitable SSPS business conditions, providing the energy keystone for a favorable future global energy, environment and economy.

Cheers, Darel Preble
Chair, Space Solar Power Workshop
Psalms 19:4-5

This idea has been around for sometime. How do we beam the power down to earth without cooking everthing around? Microwave.

It will continue to work even after a hacker captures the navigation system and fries his girlfriend's house and all her neighbors or something (e.g. a micrometeor, solar storm, cosmic ray, time, etc.) damages the gyroscope and the beam drifts off to fry a city. No thanks!!!

It is possible to capture a power satellite beam, but it isn't easy.

To get the phasing right so the beam actually focuses on the rectenna requires a pilot beam up from the center of the rectenna. To move this to a nearby city would require ripping out the encrypted transmitter loading it in a truck and driving it to a city. If someone noticed that 5 GW of power had vanished, they might get a bit upset and turn off the satellite. But assuming that didn't happen, the people in the city would get another 250 W/m^2 or about 1/4 of the energy of standing out in the sun. In the winter time, you might feel the need to take off a heavy coat. In the summer you would want to put on your aluminum foil hat.

Keith Henson

the people in the city would get another 250 W/m^2 or about 1/4 of the energy of standing out in the sun.

Less than 2X the wattage *CAPTURED* by land based PV

Come one Darel - I've posted links and shown actual numbers. Show how my numbers are wrong.

'show me how my numbers are wrong.'

That requires accepting your premise which I for one do not.

100% fuel free
100% pollution free
100% human free
Unlimited baseline energy

That is not a valid premise so why bother with the details? Unless of course this SPS stuff is 100% free, which it is, right?

I guess there are plenty of idiots with money to try it..

maybe we could look for more terrestrial solutions to our energy problem. purely a pie in the sky attempt at bau. whiz-bang.

has anybody at nasa thought about conservation ? there is plenty we don't know or don't care to know about mother earth and her inhabitants.

a politicalization/religousation of science,imo.

You mean the US tax payers? Hmmm -- we are the ones the footing the bill.
Idiot -- probably yes -- with money -- nope -- we are selling our children for this.

I guess next research material would be GN drive based on solar reactor design...

If the down beam is a narrow cylinder not a cone the focussing sensitivity will be delicate.
- people could object to a beam at night
- during daytime pilots could be blinded
- if the beam strays expect lawsuits
- needs to be switched off if it strays
- X 9.6 + night may not be enough

I like the idea of ultra cheap rooftop moving parts to go wrong, no new transmission. Daytime time cloud cover, seasonal variation and night time darkness may be easier problems to solve.

Boof, the beam would be electromagnetic, ratio waves that is, not light. There is no way to keep the waves from spreading out. Even a pencil beam spreads.

The very idea is absurd however. The expense would greatly outweigh the tiny amounts of power it would generate. It is science fiction that people just love to talk about.

Ron P.

The receiver on the right side image looks all shiny hence my assumption. I think laser light can be kept to a narrow beam. Still some sensitive ground equipment might not like an off-course microwave beam which makes the satellite a good target for the bad guys.

I still fondly remember SimCity 2000, which featured these as one of the available power plant technologies. Occasionally the beam would miss and a suburb would catch fire :-)

I guarantee you that would be a NIMBY objection, just as people will violently protest nukes because Jack Lemmon had a heart attack and there were all those bad welds and they wouldn't let Jane Fonda tell her story on the air.

I guarantee you that would be a NIMBY objection

Then build the things out on the continental shelves. Works for oil.


Darwinian -

As I recall, at least in the concept proposed by Peter Glaser, the microwave receiving array on earth would cover quite a large area, probably almost as large as the space-based collectors themselves. So, it appears to me that the spreading of the micro-wave beam has already been taken into account (though I am hardly qualified to prove this).

The proponents also argued that the microwave beam would be so dilute and have such a low energy flux that it would not endanger human or animal life that found itself within the beam. This could be true or just wishful thinking.

The beam issue you raised is probably the least of the many conceptual flaws inherent in this whole concept.

As I commented elsewhere, this whole thing has the distinct aroma of pork.

Not to mention that the industrial base required to manufacture PV and wind turbines is much smaller and simpler than that required to launch these arrays into geostationary orbit. The problem with much of our existing energy infrastructure is that it has grown so complex that many factors can interrupt supply. Are we really going to tolerate blackouts during solar maximum?

While the scifi nerd in me says "Yesss!" the rest of me says "Raise the funds, launch a prototype and prove that it works."

I a not scared by the technological complexity but by the lack of long term planning and investments as in this generation living on the hard work done by previous generations while not providing for the comming generations.

While the scifi nerd in me says "Yesss!" the rest of me says "Raise the funds, launch a prototype and prove that it works."

My sentiments exactly--almost.

This should be one of our sources of energy, but it should not necessarily be either the principal one or the most urgent.

Why not GEOTHERMAL? Free, always available, proven to work (see major cities in the Philippines, for example)--and also no CO2.

What's the plan to re-energize the Earth's core after removing the energy? What a legacy for the biosphere - "we" made sure the magnetic dymno froze up - thus allowing the solar winds to strip the planet of atmosphere.

(Ha! Take that for long term thinking!)

Thats cool, if we slow the rotation by increasing the tidal and wind friction with turbines, there will be less centrifugal force, so gravity will pulling harder on the atmosphere.

Profligacy of scale.

This concept suffers from the "bigger is better" mentality that has gotten us to where we are today. I'd rather see silicon panels become a commodity product, with neighborhood- or house-area NaS storage for overnight, and a (metal cable) grid to carry power from sunny areas to the sun-deprived. That and wind power and whatever else we can put on the grid.

IMO the molten-salt thorium fluoride nukes make more sense... (IOW not so much)

This concept has indeed been around for a long time, since about the late 1960s. If I recall correctly, its creator and chief salesman was one Dr. Peter Glaser of Arthur D. Little.

The proponents of this scheme usually cite two main advantages over land-based solar: i) elimination (well, almost) of the need for energy storage to cover periods of darkness and low sunlight, and ii) higher energy collection efficiency in terms of energy collected per day per unit area of collector.

The first is a valid argument, as energy storage and/or back-up power generation are the achilles heel of both solar and wind power. However, balanced against this major benefit is the amount of energy consumed in putting these things in orbit and the enormous capital cost. Remember how the space shuttle was touted as a low-cost way of putting things in orbit? It has turned out to be anything but. Has NASA ever done anything that has even come close to being on budget?

The latter argument of higher energy collection efficiency per unit area is somewhat dubious, not because it is untrue but because it is not all that relevant. Collection efficiency may be highly important if you are mounting a solar panel on a satellite or moving vehicle, but becomes far less important for something that is stationary, simply because there is generally no shortage of area upon which to mount a solar panel. What really matters here is average electrical power delivery capability per unit of capital investment. In other words, if you have a large open field, you might find it preferable to go with cheap inefficient collectors rather than expensive efficient ones, depending on the relative cost/benefit numbers.

And let us not forget that with such a system one not only has to have a solar collector in space but also a large microwave receiving array back down on planet earth. So, we now have two systems to pay for and worry about.

This whole thing strikes me as little more than an attempt by NASA and the aerospace industry to find a new mission, paint themselves green, and, more important, get their snouts into the feed trough for some of that green money expected to flow from the Obama administration (maybe if there's some left over after we finish giving over $10 trillion to the global financial establishment).

Maybe after enough lobbying from the aerospace industry, military-industrial complex, and congressmen from states with a large aerospace presence, some of these things will eventually get built, but it's a good bet that it will turn out to be just as horrendous an economic fiasco as the Space Shuttle.

The idea was actually first floated by Isaac Asimov in 1941 (though that was science fiction, admittedly).

You are right about Peter Glaser - he patented the idea in 1973.

Unfortunately I didn't know we had a guest post on this topic, as I just wrote and posted one of my own - which may remain exiled at ANZ :

The economics seem to be the killer at the moment - Chris Nelder calculated the cost (based on a previous pentagon estimate, though Solaren are saying they can do it much cheaper) as being 300 times what CSP would cost for the same amount of power generated.

Big Gav, I received a 'Permission Denied' message when I tried to follow the link and read your article.

I agree in spades that from my techno-geek side this idea has always been intriguing, but the cost of hauling materials up the gravity well is too much. I concur that the money/time/effort/hope is better spent on mounting PV on most of of rooftops and working out the power/load management, including conservation/efficiency/lifestyle adjustments to go with that. That course would literally not be 'rocket science'. Instead of gross subsidies to large corporations, this approach would be 'power to the people', on their rooftops...and think of the installation and maintenance jobs. Lots of vocational/technical institutes would be able to tool up to teach PV/storage/load-management installation/repair, as well as solar hot water installation/repair, ground heat pump, etc. These would be solid, good-paying jobs where people would have the satisfaction of measuring, cutting, working with their hands to build and maintain tangible, useful devices with an immediate impact on people and society...not 'PowerPoint Engineering'. Ideally, such a '100 million roof'(s[eaking of U.S. with this number) effort would be instituted with local and regional banks (dare I say Savings and Loans?) vice relying on the corrupt, bankrupt 'Masters of the Universe' wonder-boys on Wall Street.

Heading Out has an SPS piece too: Sun Power from Space, an old idea returns.

Chris, you might not be familiar with the work of Stuart Staniford, who was a regular contributor here but is currently listed as an "Emeritus." He rounded up his career here with a batch of articles outlining a progressively more high-powered future, going against the grain of opinion here to say the least; one you may find of particular interest is Powering Civilization to 2050, which details constructing a global power grid of solar arrays, with nations exporting electricity to those currently in the dark. This brought up a whole cavalcade of objections, not only technical and economic but geopolitical. Those also apply of course to SPS, which I offered up in Stuart's piece as a way of defeating the intermittency issue, which, without elaborating, Stuart said he found an insurmountable obstacle to a wholly renewable powered grid.

I really have my doubts about SPS too, actually. I only brought it up since in Stuart's vision we're spending tens of trillions per year, why not go nuts? My idea of a viable new source of energy would be the President going on TV and offering a tax break to anyone who recycles an old freezer.

My idea of a viable new source of energy would be the President going on TV and offering a tax break to anyone who recycles an old freezer.

I know that's (probably) in jest, but really. Some realism, please.

"The economics seem to be the killer at the moment "

Exactly correct. If you start with dollar a gallon synthetic gasoline, then to make that you have to get power down to around a penny a kWh. For that to be possible, the cost per kW of installed power sats have to be around $800/kW. If the power sats mass 4kg/kW and half of the overall cost is lifting them to GEO, then the lift cost has to be around $100/kg.

That's a long way up from the physics limit of about 15 cents a kg, but a long way down from the current cost based on expendable rockets. In fact it's about 200 times less.

When I worked it out, rockets were not as bad in terms of energy payback as I expected. The energy efficiency of multi stage rockets is about 3% and the energy payback is around 40 days. That exceptionally good by earth based payback standards. The problem is not the energy (fuel) burned, but the high cost of huge throwaway rockets.

The economics problem eventually comes back to the rocket equation which says you need huge mass ratios for missions that are a number of times the exhaust velocity.

To deliver 100 t/hr to GEO with pure rockets would require launching something twice the size of a Saturn V every hour.

But if you go to exhaust velocity of 12-17k/sec for a second stage (which you can get from a big laser) it only require flying a rocket the size of a 747 4 times an hour to get a materials flow of 100t/hr to GEO, cost of $100/kg, power at a penny a kWh and gasoline at a dollar a gallon.

More detail here:

Keith Henson
a founder of the L5 Society

If you start with dollar a gallon synthetic gasoline, then to make that you have to get power down to around a penny a kWh. For that to be possible, the cost per kW of installed power sats have to be around $800/kW. If the power sats mass 4kg/kW and half of the overall cost is lifting them to GEO, then the lift cost has to be around $100/kg.

$1/gal is absurdly low; if terrestrial oil supply is a problem, $5/gal will be considered cheap.

Gasoline is roughly 37kWh, so you're assuming 37% conversion efficiency, which seems reasonable. That's roughly half the efficiency that seems to be targetted for producing hydrogen from electrolysis (50kWh/kg to get (40kWh/kg) of hydrogen), so it's probably a decent guess.

$800/kW / $0.01/kWh = 80,000 hours = 9.1 years, which seems like an oddly short lifespan to assume. Solar panels on existing satellites degrade by roughly 2%/yr and are expected to last through 10-15 year missions, so 9 years is almost certainly too low for a lifespan. 20 years (after adjusting for panel damage) might be appropriate.

So we should expect roughly 200,000kWh @ $0.05/kWh = $10,000/kW, or about $2,000/kWp (assuming 20% initial cell conversion efficiency).

The article talked about 16.8kW/kg, so your assumption of 4kW/kg is oddly low, unless there's some reason why 3/4 of the satellite mass needs to be non-collecting material (e.g., superstructure, transmitter, etc.). 1/2 the mass being such "dead weight" would give a figure of ~$20,000/kg for acceptable launch costs, compared to roughly $10,000/kg for low earth orbit on an Arianne 5.

So the launch costs don't seem impossible.

(I don't think the technology is ready for a project like this, and I don't think it's the best use of resources anyway, but it doesn't seem like launch costs would be the source of problems.)

"$800/kW / $0.01/kWh = 80,000 hours = 9.1 years, which seems like an oddly short lifespan to assume. Solar panels on existing satellites degrade by roughly 2%/yr and are expected to last through 10-15 year missions, so 9 years is almost certainly too low for a lifespan. 20 years (after adjusting for panel damage) might be appropriate."

Neither Dr. Phil Chapman nor I think solar panel production can be ramped up fast enough. This assumes heat engines, perhaps mercury vapor and steam stages in series that would be 60% efficient.

There is no reason power satellites should not last for many decades, even centuries with reasonable maintenance. The target of under ten year is to make the project more attractive to investors.

"So we should expect roughly 200,000kWh @ $0.05/kWh = $10,000/kW, or about $2,000/kWp (assuming 20% initial cell conversion efficiency)."

Five cent power will not undercut nuclear reactors. For this power source to make sense of all the investment, it has to capture a very large chunk of the total energy market.

"The article talked about 16.8kW/kg, so your assumption of 4kW/kg is oddly low, unless there's some reason why 3/4 of the satellite mass needs to be non-collecting material (e.g., superstructure, transmitter, etc.). 1/2 the mass being such "dead weight" would give a figure of ~$20,000/kg for acceptable launch costs, compared to roughly $10,000/kg for low earth orbit on an Arianne 5."

You misread, I proposed 4kg/kW or 1/4kW/kg. And it might be more like 5kg/kW.

Which definitely makes existing launch cost way too expensive.

Keith Henson

I actually read the entire report published on SSP. One of the benefits which is most frequently ignored by the public is that a system like this allows the military to beam power into bases without the need for a fuel supply line. i.e. if you have a base in fill-in-the-blank-istan, you don't need to worry about insurgents or an enemy military disrupting your fuel supply lines (assuming battery operated tanks, I suppose).

This seems like the most likely reason why the government would be willing to put something like this in orbit -- the same reason that GPS was ever finished -- military advantage.

While I'm not clear on this, it would seem that beaming power to remote locations other than the primary rectenna site would be a problem. The remote rectenna would need to be quite large and thus nowhere near portable. Directing power from GEO might require an additional sending antenna as well located on the satellite. I too read thru the report and recall a comment about the majority of the energy needs of the military (in Iraq, for example) being that for transport. There wouldn't be any direct powering of vehicles with this scheme, unless they were electric powered with batteries. Forget about using helicopters and tanks.

I think that this supposed "benefit" is nothing more than salesman's hype...

E. Swanson

Watch your words Mr, who gave you right to talk that badly about countries that have a "stan" in their name? Why not you think about why your countries' looting military want to present in a "stan" country? Why not you people stay in your countries? Why not let us live? We share this planet with you, you like it or not, we have our resources which we have not used foolishly like you do even though for that we have to remain a "third world" country. Who give you right to loot our resources? Who of this land want you here?

What the hell you think the word "insurgent" mean? I think it mean intruder, like a virus in human body. Consult any dictionary and it will hopefully dawn on you that you are the insurgents, you are the intruders, you are the looters. History will God willing remember you with this name. No matter how strongly nazi germans thought they have right of "living space" in russia, no matter how strong nazi propaganda machine was, history tells us that the germans were wrong. It was not russian problem that they have increased their number and living standard.

Its past noon. Open your eyes. Smell the coffee. You are the losers in this global war. You are at the wrong side of moral ground. You are at the wrong side of technological ground, all of your "superior" technologies are just a waste of resources, you lack the mostly needed tools and technology, you lack the fundamental managerial skills and most importantly you lack the ordinary power of sightness (forget vision) to understand the difference between light and darkness, you have nothing, you are lost.

I don't think neltnerb meant any offense. Our military sometimes acts in strange ways, and he was trying to explain their thinking.

Sure, maybe his intentions were benign.. but that kind of shorthand IS offensive, especially when it's tossed off as glib. It's like movies that put guys into Turbans or Hajibs (?) as an 'obvious connotation' that they are terrorists and probably not quite up to snuff with 'our world'.. ie, subhuman.

Yes, you're right. I understand completely.

No offense was intended, I have many friends from those various -stans (although if you assume I'm some sort of evil nationalist, then presumably you'll take that similarly to how I take it when white suburbanites talk about how they have "black friends" or "gay friends"). But no matter.

It was merely intended as a comedic reference to George Carlin (I think). Perhaps it was actually John Stewart, but I suspect he wasn't the first to use the reference. As referenced, it is indeed supposed to be a subtle commentary on how the US government and the more nationalistic part of the population views the rest of the world in vague terms and lumps in has a poor knowledge of geography. Come to think of it, perhaps the reference was originally in "Wag the Dog"...

No offense was intended,

I suspect the attitude of disapproval (of the whole colonialist adventure thing), that was apparent to us English speaking Americans wasn't apparent to a non English as first lanquage person (whose homeland is subject to our flying armed assasins (Predator drones)). Sometimes even though it may seem disingenuous, you need to add comments about sarcanol. Few on TOD approve of the US's imperialist ways.

Fair enough. I nearly self-censored the statement when I initially wrote it, and I fully understand how someone not familiar with "American" culture might not be aware of the reference.

Nonetheless, I hope that my choice to take some literary liberties doesn't obscure the fact I was trying to convey -- that the application to powering remove military bases was included specifically as a point in the SSP comprehensive review done in the late 90s, and that it was very specifically talking about military bases in occupied or otherwise hostile territory. The reason for why it might be a hostile territory is not something I intended to debate, but I suspect the military is not worried about Mexico invading and the military bases in the US being the only friendly territory remaining.

The document also listed being invulnerable to terrorist attack as a major benefit -- in order to damage it you must at a minimum be able to launch ballistic missiles, or have substantial laser technology (perhaps... I'm not convinced a laser could hurt it, short of taking advantage of a poorly designed aiming system).

Personally, I think the application to remote bases is silly, for the reasons Gail pointed out -- the rectennae must be quite long in order to have the correct frequency response and quite large in order to have enough power received. Similarly, the second military reason is also rather silly, as even assuming that terrorists care, a distributed power generation system and smart electrical grid would be pretty invulnerable anyway, and much cheaper.

However, I do suspect that the only reason why something like this would ever be built is because the military thinks it would be useful. No normal civilian group would ever have the resources to waste on this kind of project.

Sorry, Erika's comments, not Gail's.

Its past noon. Open your eyes. Smell the coffee. You are the losers in this global war. You are at the wrong side of moral ground. You are at the wrong side of technological ground, all of your "superior" technologies are just a waste of resources, you lack the mostly needed tools and technology, you lack the fundamental managerial skills and most importantly you lack the ordinary power of sightness (forget vision) to understand the difference between light and darkness, you have nothing, you are lost.

Wow! I didn't know we had hellfire and brimstone preachers--or is it Imans--on his site.

As for your comments, I would suggest you look in the mirror when you utter these words.

What the hell you think the word "insurgent" mean? I think it mean intruder, like a virus in human body. Consult any dictionary and it will hopefully dawn on you that you are the insurgents


1. a person who rises in forcible opposition to lawful authority, esp. a person who engages in armed resistance to a government or to the execution of its laws; rebel.
2. a member of a section of a political party that revolts against the methods or policies of the party.

Don't tell people to consult a dictionary until you've done so first.

You are at the wrong side of moral ground.

"A suicide bomber driving a pick-up truck has killed 27 people in an attack at a police checkpoint in north-western Pakistan"

It's worth remembering that the US being in the wrong doesn't mean their enemies are in the right. It's tragic that the US's blundering has driven scores of well-meaning fools into the arms of murderous groups; nationalistic pride is not an excuse to condone atrocities. On either side.


Absolutely correct. The military will find a way to protect their energy. This is one reason I have never accepted some sort of return to the stone age. The cat is out of the bag, there are too many technical options, the military will never return to the days of pike and sword.

For liquid fuel, make no mistake, there are ways for the rich military to never run out. Nuclear power plants to melt down and extract shale? It will work. It may be expensive, but when has that ever stopped the military. It may be dangerous or environmentally a mess, but again, that is not a priority when you are defending your military's existence.


Power from space is an old dream that has very slowly come into focus - Tesla is usually sited as the first technical genius to describe and attempt to gather it, but perhaps a shepherd named David first looked up at the power of the sun rising, and wrote down poetry/prophecy (your choice) about it.

I agree NASA is not the right vehicle to bring SSP to fruition. We need a new company focused ONLY on power satellites, just as Comsat was focused ONLY on communications satellites. As Bill Stone, a great designer of robotic systems for extreme environments (and NASA contractor!) said for Popular Science, "Whatever NASA does will be cautious, timid, slow, and uninspiring."

The receiving array down on earth would be paid for by the purchasing utility on earth - not the one in space. They must have some "skin" in the game - about a Billion bucks - but much cheaper (eventually) than competing power solutions. The real crux is EROEI (Energy Return On Energy Invested). This is what will win the game in the end. That and the fact that it is far more preferable to have the power generation problems 93 million miles away rather than ten or twenty miles down the road. We only want the clean power not the waste and water issues.

It would be interesting (and perhaps mandatory) to see the breakdown of number of launches, with their payload and fuel usage to get this space solar lego working on the spreadsheet. Without those numbers i will keep on reading Asimov, he has better writing skills.

"10. Increasing energy efficiency with new technology is not an energy solution, since most technological innovations are really diversions of cheap energy into hidden subsidies in the form of fancy, energy-expensive structures.

Most of our century of progress with increasing efficiencies of engines has really been spent developing mechanisms to subsidize a process with a second energy source. Many calculations of efficiency omit these energy inputs. We build better engines by putting more energy into the complex factories for manufacturing the equipment. The percentage of energy yield in terms of all the energies incoming may be less, not greater. Making energy net yielding is the only process not amenable to high energy-based technology."

Howard T. Odum.

I suppose we should thank Darel Prebel for posting this piece of techno propaganda. There are so many holes in this that it makes one wonder whether he has any experience in the satellite business.

Where to begin? Oh, yes, he fails to dwell on the fact that the heavy lift vehicle(s) needed to launch all this mass into space don't exist. He points to SpaceX and their Falcon 9 project, which is not operational, being in the preliminary design stage. They are still working on Falcon 4 and the SSP needs to launch to GEO, which requires another stage or "space tug" to move beyond LEO...

He suggests that liquid anhydrous ammonia would make a great fuel, since it is being readily made these days. So, if this fuel is so great, why wasn't it used on the Space Shuttle? Turns out that liquid oxygen/liquid hydrogen is the best fuel, providing the most lift per unit fuel weight. Duh. Basic satellite engineering there, folks.

Or, he begins by mentioning Solaren's project, which happens to be based on concentrators and high temperature PV converters, but then goes on at length to compare SSP with conventional, low concentration PV on Earth. He writes about on orbit PV, suggesting they might be thin film, not a concentrator system like Solaren's (or, for that matter, like the graphic included).

He mentions control moment gyros and space sails for stability, ignoring the fact that the SSP would be vastly larger than the ISS and therefore much more difficult to control. Control Moment Gyros are mechanical systems, several of which have failed on board the ISS. Who's going to fix them, when they break?

He writes about the need for protection from asteroid impacts, implying that having an SSP would make it possible to "protecting us from a growing threat" to our "critical space satellite resources". OK, so this whole game is about another weapons system in space. Think of it, all that power converted to laser energy and directed toward a city or an aircraft carrier or a bunch of oil refineries...

E. Swanson

Nice reply ...

With so much money floating around, a lot of special interest groups are positioning themselves for some dough from Uncle Sam. SSP will definitely sell their "offensive" capabilities to our politicians to get the thing started. How in the world can you get a Trillion dollar military project through the American people? Did someone mention "Pentagon's estimate" of cost on this project? Hmmm -- this is why we stuck in this quagmire. A lot of resource are being wasted by our military which is just a huge tax on the environment -- at least with housing bubble, some homes are being used to live -- but those "atom" bombs and expensive fighter jets, etc.. are just burdens to human society.

Also telepresence controlled robots - has that been demonstrated as viable yet? I see that we still launch bulky heroic lumps of meat into space for some reason.

I suppose we should thank Darel Prebel for posting this piece of techno propaganda

That is one purpose of this site - to look hard at one end of the spectrum and understand what avenues don't make sense. (Of course it didn't work with corn ethanol)

Of course it didn't work with corn ethanol

If by that you mean that TOD didn't keep Congress from passing stupid Porkish legislation, you are correct. But I don't think that is the Oil Drum's mission.

The whole logic of corn ethanol was exhaustively evaluated here, and found wanting. When it was attempted, it failed, of course.

TOD is a source of information and a forum for discussion. Politics occur elsewhere.

"it failed, of course. "

Really? Then how, praytell, did that 1 - 2.5 gallons of ethanol get in your gas tank?

With an ill-thought subsidy.

Without it, would the Ethanol still be flowing?

If we weren't spending $200 Billion/Yr and 400 American Kids' Lives in the Middle East would the OIL still be "flowing?"


It is a fallacy that the US needs to be involved in the Middle East in order to keep the oil flowing. Whoever owns the oil fields will want to sell oil to make money to buy stuff. If Saddam had remained in control of Kuwait the oil there would have kept on flowing. If Saudi Arabia were to take over Qatar and the UAE the oil would keep flowing.

Let's imagine Saddam Hussein in control of Iraq, Kuwait, Qutar, UAE, Saudi Arabia, Oman, and Yemen (That IS what we're talking about.)

What do you suppose the price of oil would be?

Let's imagine Saddam Hussein in control of Iraq, Kuwait, Qutar, UAE, Saudi Arabia, Oman, and Yemen (That IS what we're talking about.)

Saudi Arabia: 28M people, $580B economy

Iraq: 28M people, $110B economy

It's not at all clear that Iraq posed a significant threat to Saudi Arabia, or that Iraq would have had any interest in opening a major war against a powerful enemy when a previously-attacked enemy (Iran) would be perfectly posed to threaten the side of Iraq farthest from those troops.

So, no, it's actually quite unlikely that that is what we're talking about, or even should be talking about. Available evidence suggests that Iraq under Hussein would have been unable to carry out conquests of major neighbours; it tried - Iran - and failed, even with US support. It's unlikely further attempts would have been much more successful.

With a lower ratio of people to oil Saudi Arabia pumps a lot of oil. If Saddam had taken over the Arabian peninsula he would have pumped as much in order to fund his larger state.

That theory was substantially weakened during the OPEC embargo. Add the possibility of Iraq or Iran gaining an effective monopoly on Persian Gulf oil and the nation felt more comfortable with an air craft carrier group or two or three and a couple of battalions of the Army in theater to help remind everybody who's their daddy.

Oil embargo: It was short-lived. The Muslim oil producers do not want to stop producing for an extended period of time. They need the money. That's key. They need the money.

So, if in 50years time, we have no oil but are driving around in EV's and still have a battery subsidy, this is a failure?

There will always be "subsidies." Oil is subsidized. Nat Gas is subsidized. Solar is subsidized. Wind is subsidized. Nuclear is subsidized. Food is subsidized. Health Care is subsidized. Bees, and bees-knees are subsidized. The internet is subsidized. Bless us all.

Don't forget the major investment banks.

The question you clearly subvert with such a broadsweep is determining which subsidies are productive, and which are not.

We subsidized the Interstate Highway System being built.. do we do it again with the validation of your above reasoning that Subsidies 'always will be..' Do we bankroll some or all of the Space Program? Are there useful and non-useful parts. And of course..

Is the Ethanol Subsidy sensible? Productive? You kind of jumped off to all sorts of other ones, but I did start with Ethanol's to look at those dollars, not any other ones...


Jokuhl, the ethanol subsidy is about $4.5 Billion/yr. I think we surely save more than that in gasoline costs due to the competition/replacement of another fuel. Yeah, I think it's worth it. In fact, I think it's a "bargain."

Your mileage may vary.


Bees, and bees-knees are subsidized.

Please inform me of the spot in IRS code that supports the claim about bees being subsidized.

Thank you.

I'm pretty sure I saw something about "bee research." Want to bet me I'm wrong?

People producing honey (or more realistically having bees do it for them) are subsidized by USDA programs.

Please name the USDA program(s) that do that.

I asked for the USDA program. Where are the links to the USDA?

This looks like it:"The Agricultural Act of 1949 (P.L. 81-439, Section 201) provided permanent authority and made available price support for honey through USDA’s Commodity Credit Corporation (CCC)."

And again - links to the USDA site with the USDA forms.

And again - links to the USDA site with the USDA forms.

Oh come on, are you that desperate for a subsidy?

As far as I can tell, the claim is bogus. So I want to see the actual USDA source documents.

(The closest is the loan program for honey at 'bout $1.50 a lbs. $2 is the wholesale price. Its not like the payment programs that corn has.)

My family ran a fairly large beekeeping business in the late '70's. I do not recall any subsidies being available at that time so you may be right.

On the other hand, it is obvious such subsidies have existed in the past, and probably should exist now due to the fundamental importance of honeybees to American agriculture.

On the whole though, I'd say that whether they are currently on the books or not isn't important enough to justify the level of work that actually finding an official reference (that may not even be web-accessible) would be, and insisting on such so intently makes you look bad.

USDA Main page on beekeeping.

No obvious credits, though I do see crop insurance provisions after a quick glance.

Took me about 3 minutes, you could have done the same and posted that link in support of your position.

On the whole though, I'd say that whether they are currently on the books or not isn't important enough to justify the level of work that actually finding an official reference (that may not even be web-accessible) would be,

It is no work if the original claim was true. If the claim was made from a basis of fact.

It *IS* work if you were making it up. Given the lack of USDA links AND the dragging up of old USDA payments - the original poster of the claim was making it up.

The original claim made no timeframe and if that is the standard - well then cops still beat confessions outta suspects (the 3rd degree) as example.

insisting on such so intently makes you look bad.

Really? Insisting on proof of claim makes someone look bad?

No obvious credits ... you could have done the same

Errr I should post 'I found no data'? I am already rather sure there is no data to support that UDSA supports bees like they do corn. My posting 'I've found not data backing your claim' - a lack of evidence is no proof of non-existance -- esp. when the claim exists that beekeeping gets 'subsisided'.

kdolliso made an off-the-cuff claim that *everything* is subsidised.

Indeed, the apicultural community benefits greatly from government money in the form of government-funded research and crop insurance. The USDA apparently has the authority to provide additional subsidies should they see a need, but do not appear to.

Nobody but you seems to have made this claim that bees get as much of a subsidy as corn, the facts of what is or is not provided is available through a trivial Google search on the USDA website.

You come across as really upset about a position that nobody is taking, and very demanding that they come up with a proof for a position that you have foisted upon them without apparently being willing to put up the obvious link that shows that you are right. A link that is, in fact, the very one that shows exactly what subsidies *are* available to American beekeepers.

And you wonder why some people have trouble taking you seriously?
Missed that John Kutz post three times now. He does seem to be making a stronger claim, you still seem unduly upset about it, and posting the link I provided would have been a much stronger argument than any you did make.


Since you have not offered a substantive reply, I take it that that you agree with my comments...

E. Swanson

Hi Black Dog,

Most of my degrees are in physics, most of my experience is advanced systems design and development and strategic planning for a large electric power company. I left there in 1997 to start the space solar power workshop, after years of talking and presenting with experts in the many component fields in SSP technologies. Other questions -

Launch - Products are built for markets that exist - including launch vehicles. RLV's for SSP will be built for SSP when a company orders them.
It might be argued Falcon 9 is operational, since Falcon 9 uses the same engines, structural architecture, avionics and launch system as Falcon 1 - which flew last year. Three Falcon 9 flights are scheduled this year, four next. Spacex has the largest launch manifest in the business.

Liquid fuel - The issue here is finding a replacement for liquid fuels, since fossil fuels are facing decline. Liquid anhydrous ammonia is one viable candidate synthetic fuel, since it is being readily made, shipped and used. Others exist. Finding rocket fuel isn't the problem, their cost/performance box provides greater options than powering airplanes and cars - finding energy and chemistry to replace fossil fuels is the question.

SSP design - Yes, both Solaren's design and the ISC design shown use concentrators. And both would probably use thin film as well, since it has the highest output per kilogram, although not the highest energy conversion efficiency.

Control moment gyros - Telerobots will do all maintenance on SSP satellites, including CMGs. GSO is far too dangerous (hi radiation) and expensive a place to keep people working there. Many other control mechanisms will probably be used - the solar mirrors and panels them selves, gravity gradient stabilization, DS4G or better ion-drives, etc., The key thing to know is that the equations of interaction between the earth's magnetosphere and solar flares have been solved. That means we know how to model, design, and then fly an SSP. Lots of work - but we understand how to do it. Most of the systems have already been done in smaller scale or other formats, like CMGs.

Asteroid impacts - SSP would NOT "protect us from a growing threat" to our "critical space satellite resources". NASA spends $3 million a year loooking for asteroids that could strike earth or space assets next week. They spend $300 million looking for earth-like planets in our galaxy. I think this is an improper allocation ratio. The "Deep Impact" movie shows this fairly well technically -

SSP's would not use lasers to transmit power, as sun-pumped lasers are not efficient enough to be considered without MUCH more work. More importantly, the systems likely to be used, use a coded guide beam from the rectenna to the transmitter. If the delivery beam strays a little off, the guide beam tells it where to move. Too far away and the lock is lost and the beam shuts down - no one wants power delivered where it won't be paid for.
Solaren's plans, like most, envision using using microwave - these have a long well understood history and proper regulations to boot. Your cell phone, cell towers, microwave oven, and hundreds of other commercial devices use microwave.


From your description of your background, I see that you have not worked in the aerospace field nor do you mention any such education either. I was employed a bit in the satellite field, working on attitude control systems for a few years in the late 1960's, then later worked on the design of the ISS thermal control system in the mid 1980's. I also briefly studied in the aero & astro department of a major university. BTW, I got my BS degree at GaTech and have had several run ins with the local electric utility over their nuclear power plants. Remember back in the early 1980's when Ga Tech had their own solar thermal tower concentrator set up out in the sunlight, as well as a small wind generator? When the price of oil fell, these demonstrations came down too...

Your lack of expertise was clear when you suggested ammonia as a "green" fuel, when H2 and O2 are very good fuels with little direct impact on the environment. Both can be made from ground based PV using DC electrolysis and the PV array might be located near the expected launch site in Florida. Better yet, the combustion product is water, which is harmless to the local environment near the launch site and to the Earth's atmosphere as well. Not to mention that the H2/O2 combination is one of the best fuel combinations for rockets.

I am aware that Solaren's proposed SSP uses concentrators. There are pluses and minuses with this approach and you appear to be glossing over some of the minuses. With a concentrating system, the power output per kilogram sounds great, especially if you ignore the mass of the reflectors and associated structure. And, where's the allowance for the mass of the cooling system needed to keep the PV portion of the system from melting at 100 suns energy density? On the ISS, most of the energy captured by the PV arrays and delivered within the ISS must be removed by the thermal control system. But, that amount is only a fraction of the solar energy which hits the PV arrays. With a concentrator system, the energy which is reflected toward the PV array is either turned into electricity or removed by a thermal control system. A lower efficiency PV conversion results in a necessity for more thermal energy dissipation, thus the thermal control system must be larger. All that energy must be removed with an active system, meaning pumps and pipes. Better sharpen your pencil and do the calculations...

I never suggested that the SSP would use lasers to move the energy to the ground. My comment was related to the "need" to defend such an expensive and vulnerable installation, thus the military imperative to add some sort of weapon. Only a laser type device could be expected to respond to a dedicated attack using multiple rockets. Any defensive weapon also has offensive capabilities. Do you really want to start another arms race much like that involving nuclear weapons which has bedeviled the world for more than 60 years? I certainly hope not. Please remember that the scientists who developed the first nuclear weapons later regretted doing so as proliferation took on a life of it's own. Of course, the military/industrial establishment loved it...

As for microwave transmission, we may know the physics under controlled conditions here on the ground, but do we really know that it's possible to transmit energy from 22,500 miles away and recover 90% of it? What about atmospheric distortion and absorption? OK, so the transmission beam follows a guide beam coming up from the ground, but there's a time lag between the ground emission and GEO and another time lag on the return transmission of the energy. The aiming of the downward beam can not respond to any changes in the atmosphere which occur during those lag periods.

While we are at it, what will happen to these rectennas when a thunder storm passes overhead and lightning strikes nearby? Think of the local EMP or the effects of a large, high voltage spike on all those diodes in the rectenna, not to mention the electronics in the inverters. I've had some real fun experiences with lightning and well know that it can do things which you don't expect. Where's your analysis of that problem, Mr. Physicist???

E. Swanson

PV concentrators for SSP would likely be chosen to minimize maintenance costs while maximizing power output. You don't want active cooling, in my opinion, since it is maintenance intensive, as you know. That means the concentration level would likely be low perhaps 5 or 6 to 1. If amorphous silicon is used that would keep the heat levels low enough not to damage the PV fabric - the CP1 backing is pretty tough stuff, as the wiring must tolerate occasional micrometeorite strikes.

Microwave transmission is well understood. From 22,500 miles away we expect that upwards of 85% of it could be recovered. The frequency is chosen at minimal atmospheric distortion and absorption.
The time lag between the ground emission to GEO and another time lag on the return transmission from GEO is 0.242 seconds. What we are really measuring however is any beam drift off center. That can be communicated in half that time - 0.121 seconds and since steering is electronic that is orders of magnitude more time than needed to adjust the beam. We have deep experience in this area, which was developed for communications satellites. Our friend Naoki Shinohara is a world class expert in this area - he generously wrote a chapter on Microwave Power Transfer for our SSP Workshop, which I can recommend to you. You will find that chapter at

The military aspect is merely a function of the fact that all public utility infrastructure must be protected - whether from meteors, solar flares, lightning or other objects of undetermined origin. Defense from lightning (Florida is the world capital of lightning strikes), for example, is well understood, as a result. Perhaps you have visited Ga Tech's world class lightning research center - NEETRAC
IEEE had a great field trip there some years ago. Fascinating work they showed us.

Probably the worst terrorists attacking our public utility infrastructure are squirrels, ants, trees, etc., The list would be different in GSO, but the same function is necessary. I assume you are not suggesting we not defend these properties, Black_Dog?

Darel, continuing the discussion about thermal control.

Your original post mentions Solaren, who appear to be using a greater concentration ratio than the 5 or 6 to 1 you suggest, judging by looking at their patent (U.S. 6936760 - Space-based power system). The Solaren patent is so general that it would cover a wide range of implementations, so it's difficult to say what they actually want to do, given that the drawings aren't to scale.

The Heliosat system is not PV, but based on a thermal cycle. The design from Space Energy looks a lot like the graphic in your first post, but with higher concentration if I'm interpreting the graphic correctly. The images from the Space Island Group don't show anything that looks like a SSP system. Powersat's web site shows a 1x PV array, which means lots of wires but minimal thermal control requirement. Welsom Space Consortium also appears to be using a 1x PV array of thin film material.

For curiosity sake, what would be the temperature of a passive radiator with 6x concentration? As I recall, the "viewing geometry" of the radiator adds quite a bit of complexity, since there would likely be two radiating surfaces, not one, so I will use a view factor of 1.5. Thus, assume the radiating area is 1.5x times the collection area, so the energy emitted would be 1,345 w/m^2 x 6 / 1.5 or 5,380w/m^2. The Stefan-Boltzmann equation for a blackbody is:

E = sT^4, where s = 5.67 x 10^-8/m^2/T^4

If my math is correct, that equation suggests a radiating temperature of about 555K or 282C. The PV modules would be hotter than that, since there would be some insulating effect due to the distance between the illuminated PV surface of the array and the emitting surface. At 10x concentration, the temperature goes up to 631K or 358C. At 20x, the temperature is up to 829K or 556C, which is rather hot, I think.

As for lightning, I once saw a video about the Florida test site. I think their focus is the effects on single wires, such as power lines or electrical sub-stations, not a large array covering several square kilometers. I really liked the technique of sending small rockets up into a thunderstorm while trailing a wire out behind to "catch" a lightning strike at the test area. At some point in time, I would surely like to see a small test array, covering perhaps 10 acres, subjected to one of those strikes. If that work hasn't already been done, maybe I should write a proposal to NASA...

E. Swanson

It is hard to see SSP having a realistic advantage of an earth based PV system. Perhaps we can have a demonstration SSP system ready in 50 or 100 years. However, if we do not do something in the short term (2010-2020) most people will not survive to see the long term.

Nuclear power works, as does wind. If we gear these up massively and quickly we just might avoid catastrophe.

Financial collapse is probably unavoidable at this point because we lived a delusional fantasy about economics for too long, only to reach the absurd under the current administration.

this idea is so stupid that i wonder, why we are confronted with it here in this forum. its below our niveau.

The Price, or the energy input to take one kilogram of material in the space is around 100,000$. this will never be an working idea, even if downbeaming of the energy would be possible.

Everything in the outer space takes much of money, energy knowledge, and even much time. Its mostly impossible to repair anything out there, even after 2010, when NASA would stop its Program with the shuttles. I don't believe, that after this time a new shuttle will built ever...

And thats the end of every dream of outer space. We will never reach mars, we will even not reach moon again. Theres no useable Reward, and therfore no government after Peakoil will have the courage to do something like this.

And this is really good. It was a bad idea from the beginning. Humans should not fly in the space, it makes no sense.


We are looking at a problem with no easy solutions. We need to at least understand what is being proposed. Clearly the military has had some interest in it over the years, so there must be at little behind it. I notice that the Space Solar Power Workshop web site is at a GA Tech University web address.

The US military has also been interested in bats carrying bombs, nuclear-powered bombers that could stay aloft forever, LSD to make psycho killers, and gay bombs.

Thus US military interest is hardly a guarantee of the brilliance of an idea.

Don't forget Operation Northwoods for military ideas that got floated, supported, then shot down.

Only to get reused years later :-)

(and on that note, I see Ruppert has a new book coming out...)

The Price to put one Kilogram in orbit is calculated around 9 to 20 kWh/kg, depending on orbit, e.g.

Since we pay about 10 cents per kWh here in the US, that's about two dollars at most (energy cost as you claim)to place a kilogram in orbit. You are about 5000 times too high, belerophon.

Repairs in space have been done many times and we are getting much better at it. Many experts wanted to repair the Hubble with Telerobots, but NASA wanted to use astronauts.
NASA, as I mentioned borrowing Bill Stone's quote (posting to Joule), is not the right outfit to be building commercial gear in space. They were not chartered to do that and have fought commercial space frequently, such as the many groups, e.g., the SpaceIslandGroup, which wanted to use the shuttle's external tanks. Changing that perspective is slow, but there is hope, as the COTS contracts are doing.

While people should not "bolt SSPs together", there is every reason to expect that people could build settlements on the Moon with telerobotic support, enabling space manufacturing for commercial ventures, beginning with selling raw materials and bulk parts like PV to an SSP company. As I mentioned, the SSP company should have NO financial interest beyond their SINGLE focus - delivering clean power to Earth.

Actually belerophon's error in energy cost to orbit is 50000 times too high. slight correction.

When I first heard about this idea years ago I thought it was the dumbest space project I ever heard of! But it does hold some interesting uses.
Where this type of power would be useful would be for isolated areas like a military base in Afghanistan or power to a small island.
This is a very immature concept, only recently have experiments been tried in using microwaves to transmit power any distance and in these experiments no power was actually transmitted.
The component technology is well proven. Phased array radars are able to transmit enough power to be used as offensive weapons.
This sort of project would require a Saturn class rocket to haul all the hardware into orbit. It would be a brute force type of project requiring a ton of money. However the flexibility of the system would have it's advantages.
In the end I don't think you will ever see this project go beyond the talking stage.

" Where this type of power would be useful would be for isolated areas like a military base in Afghanistan..."

you use the term useful loosely.

The history of wireless power transfer is not recent - in 1893 Tesla demonstrated the illumination of vacuum bulbs wirelessly (without any wires connected to the bulbs) at the World Columbian Exposition in Chicago.. In 1975 Bill Brown transmitted tens of kilowatts across the valley at Goldstone, CA.

"Wireless Power Transmission for Solar Power Satellite (SPS) (Second Draft by N. Shinohara), Space Solar Power Workshop, Georgia Institute of Technology

Brown., W. C. (September 1984). "The History of Power Transmission by Radio Waves". Microwave Theory and Techniques, IEEE Transactions on 32 (Volume: 32, Issue: 9 On page(s): 1230- 1242 + ISSN: 0018-9480): 1230. doi:10.1109/TMTT.1984.1132833.

Large rockets are the wrong ticket to lower the cost of space transportation. That is done by high volume - like the airlines - that typically means smaller rockets.

Seems far-fetched.
Space solar is REALLY stranded energy. No way to get power from there to here. Laser beams? Too weak. Microwaves?

For earthbound applications a large area 10 km diameter receiving array allows large total power levels to be used while operating at the low power density suggested for human electromagnetic exposure safety. A human safe power density of 1 mW/cm2 distributed across a 10 km diameter area corresponds to 750 megawatts total power level. This is the power level found in many modern electric power plants

Okay, so 10 km diameter =78.4 million square meters. At 100 w/m2 for ordinary solar PV array and assuming a 20% capacity factor that's an average power output of 1568 MW which is still twice the energy of the
microwave rectenna with multiple kilometer size pieces of orbiting space junk.

Hwvr, std. solar only gen's for 4 hrs / 24 hrs.

Which just means you have to buy a couple more of them.

and I get a good bit more than 4 hours from mine.. Peak Production is not the only 'useful' production.

With geosynchronous orbit at 22236 miles you are moving at 6877 miles per hour trying to rotate concentrating mirrors kilometers across to redirect sun rays while keeping the emitter properly aligned with the rectenna.

Sounds more like a Solar Sail

Thanks for this post -- I was curious about the latest thinking after the PG&E announcement.

I have to ask, though: wouldn't you get most of the same benefits from very high altitude blimps or dirigibles coated with thin photovoltaic material? Float them in the stratosphere, direct a fraction of the harvested energy to station-keeping, and beam the rest down. Half are always in the dark, but these balloons would be cheap to mass produce, so there would be millions of them.

What kills the SSP idea is the problem of accelerating masses to orbital speed, which requires vast quantities of energy. Use balloons instead, and you get high-altitude lofting for free.

I have to ask, though: wouldn't you get most of the same benefits from very high altitude blimps or dirigibles coated with thin photovoltaic material

The touted benefit of nighttime power with no seasonal dependency would not be delivered by such a solution. However, I think your idea makes much sense as a much lower cost way to demonstrate if the technology works. Of course it will never scale to the needed size -the worlds supply of Helium is actually quite limited, but that doesn't mean it wouldn't be useful as a technology development platform.

Solar power from balloons | Party time! | The Economist From March 5.

Cool Earth’s balloons are rather larger than traditional party balloons, having a diameter of about 2½ metres (eight feet), but otherwise they look quite similar. The solar cell aside, they are ridiculously cheap: the kilogram of plastic from which each balloon is made costs about $2. The cell, the cost of which is a more closely guarded secret, is 15-20cm across and is water-cooled. That is necessary because the balloon concentrates sunlight up to 400 times, and without this cooling the cell would quickly burn out.

Like a conventional mirror, a solar balloon of this sort must be turned to face the sun as it moves through the sky, and Cool Earth is testing various ways of doing this. The focus of the light on the solar cell can also be fine-tuned by changing the air pressure within the balloon, and thus the curvature of the mirror.

The result, according to Rob Lamkin, Cool Earth’s boss, is a device that costs $1 per watt of generating capacity to install. That is about the same as a large coal-fired power station. Of course, balloons do not last as long as conventional power stations (each is estimated to have a working life of about a year). But the fuel (sunlight) is free. When all the sums are done, Mr Lamkin reckons his company will be able to sell electricity to California’s grid for 11 cents a kilowatt-hour, the state’s target price for renewable energy, while still turning a tidy profit.

Icarus, anyone?

What kills the SSP idea is the problem of accelerating masses to orbital speed, which requires vast quantities of energy.

I'm not an expert, but this doesn't appear to be true.

"Right now, it costs a thousand times more to put an object into space than to fly it across country by commercial airliner, even though the two jobs require roughly the same amount of energy--about 10 kilowatt-hours per kilogram of payload."Link

Is there supposed to be a distance component in that statement, or are they discounting the energy required to move the vessel, crew, fuel etc.. and just prorating for the payload?

The fuel is the cheapest part of space flight. If all that mattered were the fuel, many of us would be having holidays on the Moon or Mars.

To understand the difference between travel in a jet and travel in a spacecraft, imagine how much a jet flight would cost if after each flight they threw the jet away.

This is why the strong interest in reusable launch vehicles. However, it turns out that the maintenance of RLVs is as much or more than just building a new one - see the Space Shuttle.

Of course we can imagine a much better-designed RLV than the Space Shuttle - hard to imagine a worse-designed one. But then we're looking at another 10 years or so to design, develop, test and deploy such a thing. And another several tens of billions of dollars.

Which seems like a lot of hassle when we could just build power stations on the ground. What problem is this a solution for? Is there a lack of empty space to put large power stations? Then where would we put the space-based solar receiving stations?

It's like putting fission reactors in orbit. We could do it, but what for? What is gained for all that trouble?

Can I ask a basic question?

Most of the problems of re-entry seem to be heat dissipation. Clearly this is a difficult problem, but why? A high-altitude glider can dissipate heat slowly as it comes down - why can't a shuttle do that? I suppose orbital velocity is part of it, and the potential energy that has to convert to kinetic energy by the time you go from a geo-stationary orbit to the edge of the atmosphere....

Hmmm. Seems like you could kill two birds with one stone if you could somehow transfer the kinetic (horizontal and vertical) energy from an incoming shuttle to an outgoing shuttle...

if you could somehow transfer the kinetic (horizontal and vertical) energy from an incoming shuttle to an outgoing shuttle...

That will be the next post of the SSP supporters - the giant teeter-totter for the shuttle.

"the giant teeter-totter for the shuttle."

I'd envision something more like a giant rubber-band: the incoming shuttle catches the outgoing shuttle in it's trailing band, and slows down as the band stretches, accelerating the outgoing shuttle.

Know where we can get a giant rubber-band that can handle a shuttle at 20K MPH?

Most of this is from memory, so take it with a grain of salt and do your own research; I don't vouch for the exact numbers, just the general thurst of the thing will be in the right direction ;)

It's the velocity, as you say. It's going at something like 8.2km/sec from low Earth orbit, and has to slow to something like 0.1-0.2km/sec to glide to a stop on a runway, or splash in the ocean or down on the ground with a chute.

The thing has to lose quite a lot of energy. You can do that in three basic ways, apart from just plunging into the atmosphere and relying on your re-entry tiles or ablative shielding.

The first is to have rockets which do burns to slow you down so you drop out of orbit. In theory you could do it so you lose all 7.6km/sec, and just glide gently to Earth as you describe. But then you'd need as much fuel to deorbit as you used to get up there. So in practice they carry enough fuel to lose just enough velocity to drop them to a lower orbit, where the orbit enters the atmosphere - around three minutes of burn losing 90m/sec of velocity for the Shuttle, for example.

The second way is by "skipping" across the atmosphere.

The skipping is pretty rough on the vehicle and occupants, so it's really only good for single-use vehicles, or for unmanned space probes. It's also pretty sensitive to trajectory - aim too high and you get an early and too-fast re-entry, aim too low and you skip right off and get stuck in orbit.

The third way is by a series of S-turns, which is what the Space Shuttle does. As they turn to the right they present the underside of the Shuttle to the air smashing into them, and this is a lot of resistance, so they lose velocity. But if they kept in that direction they'd end plunging in backwards, which would have an unhealthy result, so then they turn around to the left, and so on - thus the S-turn. Once they hit about 120m/sec they stop the turns, pop up the flaps to slow them some more and glide in for their landing.

It's actually pretty hard to make a reusable launch vehicle. The Space Shuttle was originally supposed to have around 100 flights a year - 10-12 for each craft. In practice they never managed more than 9 a year, and 5-6 was more typical, for 1-2 flights per craft per year.

The thing is that whacking something into space takes a lot of energy. Which means a lot of heat, and machinery exposed to a lot of heat gets worn out. So after use, it has to be pulled apart and lots of stuff tuned up or replaced.

SpaceShipOne - which can't reach orbit - solves the maintenance problem by simply replacing the entire engine between flights. It's a lot harder to do that with a more complex engine such as required for reaching and leaving low Earth orbit, putting satellites up there, and so on.

This sort of thing can be done, but it's bloody hard. There's a reason we're not holidaying on the Moon.

"The thing is that whacking something into space takes a lot of energy. Which means a lot of heat, and machinery exposed to a lot of heat gets worn out. So after use, it has to be pulled apart and lots of stuff tuned up or replaced. "

hmmm. So your feeling is that it's not primarily the wear and tear of re-entry, but the wear and tear of getting up there in the first place?

That sounds like a materials and design problem. Perhaps not easy to solve in the near-term, but in theory amenable to solution through better materials (e.g., high temperature ceramics) and designs. IOW, there isn't a fundamental energy-related barrier to cheap space flight.

The energy of launch can be supplied fairly cheaply. Even with really difficult fuels like liquid hydrogen and oxygen, fuel's the cheapest part of space travel. As I said, if fuel cost were the only issue, we'd all be holidaying on the Moon and Mars already.

It's the wear and tear of using the engines, combined with the wear and tear of insulation and so on - it can be +180C on the sunny side and -180C on the dark side of a spacecraft, those temperature variations make things expand and contract and degrade and so on.

Just as a jet plane needs more maintenance than a propellor-driven plane, an office's server needs more maintenance than someone's laptop, and a racing car more maintenance than a city runabout, so too with craft designed to go to space. The more energy you put through a thing and the more you ask of it in performance, the more maintenance it needs.

So really it's not fuel, it's labour.

an office's server needs more maintenance than someone's laptop,

No. Because servers don't move around, temp control and better power supplies (move to a telco style 48 VDC - one becomes immune to AC spikes) a server will last longer than a laptop.

Now the COST of failure of a server exceeds the typical users laptop, the preventive maintenance is usually paid for. By the time the cooling fan goes in a laptop something else like a worn hinge or other broken do-dad will have killed the average laptop. Not so with a server.

If servers don't require more maintenance, I do wonder why all those people are employed in maintaining them, as opposed to the zero people employed in maintaining my laptop.

I guess that thanks to your information, we can now sack all those people. I'll tell my woman working at an engineering firm to tell HR, and tell my mates working in IT, too.

Thanks, you just saved those companies millions!

"The more energy you put through a thing and the more you ask of it in performance, the more maintenance it needs. "

Well, that makes sense as a rough rule of thumb. OTOH, it's not a law of physics - it's entirely amenable to improved materials and design.

It may or may not be worth it to go to the effort to design reusable shuttles that are cheap enough to dramatically lower the cost of space flight, but I see no reason, a priori, to assume that it's not possible.

As I look back at your posts, I see that you agree: "Of course we can imagine a much better-designed RLV than the Space Shuttle - hard to imagine a worse-designed one. But then we're looking at another 10 years or so to design, develop, test and deploy such a thing. And another several tens of billions of dollars. Which seems like a lot of hassle when we could just build power stations on the ground. What problem is this a solution for?"

Hmmm. So, what is spaced based power a solution for? I suppose the only sensible answer is that it might provide more diversity in power supplies.

The single largest question about renewables is intermittency. I think that this isn't nearly as hard to solve as many suggest, but space based power appears to not have that problem.

Yes, it's just a general statement, not even deserving of the phrase "rule of thumb." Just a strong tendency.

The issue of renewables being intermittent isn't nearly such a big deal as people often say. Assuming no great breakthroughs in technology or anything really expensive (like huge battery banks), it's dealt with by,

- diversity in supply; it may be overcast today but it's windy, etc
- since solar PV and wind depend on the weather, with weather forecasts we can make best use of high supply in one area to compensate for low supply in another; we already do this today, for example with Tasmania sending hydro power to Victoria on rainy days, and Vic sending coal power to Tas during droughts
- some renewables, such as geothermal and hydro, provide energy on demand
- some renewables, such as tidal, provide energy according to a schedule we can predict months in advance, and we can adjust our demand to fit the supply (especially if much of the demand is from industry)
- one renewable, solar thermal, lies between the last two, in that it can store a day or so's worth of energy without trouble
- pumped hydro can also act as energy storage, but with climate change like hydro itself this isn't a big prospect globally; some areas will be able to make good use of it, though

As to SSP adding to this diversity and offering baseload, this speculative article gives us no figures for cost or building time, number of launches and so on. So we're unable to judge it on its merits and weigh up $/time costs for SSP compared to others, still less able to judge whether it could make a significant contribution to the overall electricity grid.

As I noted earlier, it's taken more than a decade just to build the International Space Station, and it's not actually finished according to the original plans - they just changed the plans to be less ambitious. And that's only in Low Earth Orbit. An SSP station would be a task of similar difficulty - technically easier because it's unmanned, but harder to assemble and maintain because it's unmanned and in geosynchronous orbit.

When I go to the shops and find no price tags on things, or see custom orders offered with no timeframe, I know that the thing is going to be very expensive and take a lot of time compared to something off the shelf from some other store.

So I think it's fair to say that we can expect SSP to be absurdly expensive and take a very long time compared to any of the current commercially proven entirely renewable options such as geothermal, hydroelectric, solar PV, solar thermal, tidal and wind.

I agree that the problems of intermittency are overstated (I would also note the value of demand management, especially with PHEV/EV charging).

SSP certainly looks like a chicken and egg problem. OTOH, I like the idea of expanding space exploration, and anything that helps that would help SSP, and vice versa, so I remain intrigued. I suspect the same sentiment explains a lot of the interest showed by others.

I suspect Steven Chu would love this idea.

More pie-eyed sci-fi for the ivory tower rich guy.

If we are lucky, financial collapse will happen quickly enough to prevent us from wasting resources on this technotard boondoggle.

This post reminds me of Boondoggles to the Rescue! by Dmitri Orlov.

Apparently he saw a lot of these as Russia collapsed.

Nice idea, but ALL solar cells fail eventually. That eventually depends greatly on temperature and other radiation loads. Since geosynchronous orbits are a long way from the earth's surface, there is a LOT of energy to be paid to get the solar cells to orbit (never mind the energy to build the high quality solar cells in the first place - can't use organic photovoltaics!!). Also, when cells fail they will have to be replaced. Since your repairman (even a robot) has to travel to 36,0000 km above the earth to repair/replace failing cells, there is a LOT of energy to be paid to deal with THAT problem. Finally, how efficient is the transfer of solar electricity to microwaves and back again and the efficiency of transfer of the microwaves through clouds? All of those processes lose energy (lots of it). The business plan for such a technology would need to take all this into account. I would love to see realistic numbers for all of these losses.


The PV cells leading the pack for SSP consideration today are amorphous silicon. These were flown on MIR for 19 months (before MIR was crashed into earth intentionally). They had almost the same power after 19 months as when they started. After careful examination they discovered that they were re-annealing in space - self healing! - apparently due to the high operating temperature. No one really knows how long such cells will last in space but they are clearly radiation hard and solid contenders. Clearly an SSP company would try to minimize maintenance costs by using such low-maintenance-cost cells. PV cells on commercial satellites just run out of station keeping fuel after ~ 15 years, the photovoltaics keep going beyond 15 years.
Amorphous silicon also has the highest performance per mass - kW/kg - which minimizes cost to orbit.
Another technology, CIGS, are hard on their heels after them, so there is good competition. There is a chapter on the website summarizing photovoltaic technologies for SSP. It is a moving target, of course.

IMO, this is a wonderful idea , which if implemented, could significantly alleviate many of our energy problems. But on brief consideration, the potential obstacles become quickly overwhelming. It’s difficult to see how we can practically cope with all of them. Here are some of the problems, some of which are already mentioned in other comments.

First, a truly massive long-term investment would be required, based on an almost faith-based assumption that all the elements can be successfully accomplished, within an approximately equivalent and realistic timeframe, and as well, that a stable flow of funding can persist to see the project through to completion, i.e., the construction of at least one durable and reliable working model, in order to demonstrate its feasibility. Assuming that the funding can be obtained and guaranteed going forward, what are some other potential problems?

Do we currently have sufficiently thin and ultra-light materials (polymers?), with the ability to reliably unfurl into massive reflectors, and the additional ability to resist high energy UV, and other unfiltered solar radiation to which they will be continually exposed, for periods of 10, 20, or 50 years? If not, can we realistically develop such materials? If the material’s life in the space environment is limited to 5 or 10 years, for example, how can such a reflective membrane be replaced without scrapping the entire system? Can a reflector system be built sufficiently large, but light enough for realistic launch capability, while still able to maintain stability and precision focus during exposure to solar wind, and necessary station-keeping adjustments?

Do we have ability to construct a device to convert the reflectively focused light and heat energy into electrical energy on a gigawatt or terawatt scale, while avoiding rapid thermal destruction of the device? Water-cooling may not be practical in space.

Do we currently have technical ability to continuously propagate microwave energy on a gigawatt or terawatt scale? If so, can this technology be adapted to the low mass and high reliability requirements of such a project? Can it be accomplished without superconductors? If not, do we currently have ability to produce high temperature superconductive materials to handle the necessary current, without resultant unmanageable heat due to electrical resistance?

Can such powerful microwave beams be sufficiently focused to concentrate most of their energy on a pinpoint-sized (from the spacecraft’s perspective) antenna / rectenna on the earth’s surface, a distance of 36K km, or more? Can we manage to avoid excessive, both wasteful and potentially dangerous, microwave exposure to surrounding areas? What will be the effect of atmospheric humidity and clouds, since water is an excellent absorber of microwave energy?

While it’s relatively easy to imagine automated assembly of such a system in space, does available robotic technology permit sufficient flexibliity for problem-solving and resolution, when things inevitably go wrong? If not, human service calls are going to be difficult and expensive. Maximum Space Shuttle altitude, for example, is only about 1 – 2 % of geosynchronous altitude.

While a small prototype system could perhaps be launched at great expense with existing technology (if not existing launch vehicles), the energy cost of launching multiple systems would be truly overwhelming. The use of a magnetic launch system, or mass driver, is suggested as a possible solution, acknowledging the impossibility of implementation of a “space elevator” within a reasonable time. But has anyone yet used a magnetic launch device to successfully place even a one kg payload into low earth orbit, let alone build a giant device capable of launching delicate and heavy cargoes? Can a complex SSP system be designed to withstand the huge accelerative stresses and frictional heat of such a hypothetical launch? Can a sufficiently large ground launch system ever be built to withstand both the huge momentary current flux and the physical stress of rapidly and safely accelerating a heavy payload to orbital or near-orbital speed?

The idea of SSP is unfortunately predicated on the assumed availability of several essential components which are currently impossible (at least based on this writer’s level of knowledge). If there is no technical solution or practical workaround to even a single one of the essential problems, the entire project will fail. Not the least of the problems would be maintenance of sufficient and stable funding over the multi-decade period required for its hypothetical development and implementation, as we collectively experience the unpredictable effects of an accelerating decline of world FF production.

None of the following is taken to imply any magic/perfect solutions to the serious problem of reengineering the world's energy supply off fossil fuels.
I'd love for SSP to work, if only to keep enough space capability to fend off the next asteroid ...
but Evan J has mentioned many of the issues.

Beyond that, I'd recommend, found via SSPW website:

1) letter said:

"The extremely successful COMmunications SATellite (Comsat) Act chartered in 1962, was also such a public/private corporation. Just as COMSAT opened space for communication satellites, so a Sun Satellite (SunSat) Corporation Act can open space to power satellites."

I have a historical problem with that comparison. Bell Labs (where I worked for a decade) invested a lot of talent and money, driven by John R. Pierce, to do Echo and Telstar. British & French telecom organizations built ground stations. Telstar work had been started in 1959, and it launched July 1962, and proved the concept practical. AT&T paid NASA $3.5M for the launch.

Pierce says:
"A higher power intervened. On August 31, 1962 Congress passed, and the president signed, the Communications Satellite Act, which gave a new organization, COMSAT (Communications Satellite Corporation) an eternal monopoly of United States participation in international communication satellite transmission."

Basically, the concept having been clearly proved, Congress created COMSAT. This seems slightly different from massively funding SUNSAT to tackle a much bigger array of challenges.

2) URSI paper discusses many issues as does and Boeing presentation Feb 2009, both of which offer useful numbers.

3) Finally, Darel's January 2009 presentation is useful in calibrating this, but it has some issues that do not encourage credibility:

Now, I understand advocacy, and I'd be happy to see disciplined R&D done on this, but...

Slide 7: quote James Hansen on the urgency of doing things very quickly... when it is just really hard to believe that the whole set of issues laid out in the URSI and Boeing notes can be solved that fast. If one thinks it's important to do something fast, one ships&scales what already works, or is already going down the cost/volume learning curve, and keeps doing R&D on other things. One does NOT "schedule breakthroughs."

Slide 8: SSP is shown to be superior to every other power source. I know that kind of chart, I've done many of them :-) BUT:

a) Wind power is dismissed as intermittent, no good for baseload. With appropriate grid and geographic dispersion, one can use some fraction of peak as baseload. (Archer&Jacobson), and of course, it is a very good match with large hydro.

If one examines the Boeing presentation, satellite orbits pass through Earth's shadow... There are different sets of issues for LEO, MEO, and GEO satellites. 99% availability for GEO may be OK, but you do lose it for up to 70 minutes. (See p.30 of Boeing. Also see p19. for satellites already in GEO orbit.

b) Geothermal is reliable where it is, it's just that it's not available everywhere.... but neither is SSP. See p.29 of the Boeing presentation, which observes that elevation angle constraints matter, and shows an example for a GEO. They think a 30degree angle is the limit; others think 60degrees. Maybe smarter antennas help ... but it does matter where you are, just like it does for ground solar.

c) Ground solar is indeed difficult to use for baseload, but is load-following, and it meshes with hydro, although in different ways from wind. [I.e., during the day, prefer solar, get whatever wind you can, save the hydro. At night, use the wind (often better at night anyway), and fill in with hydro.]

d) Hydro isn't available everywhere, and droughts will get worse in some places, but hydro not only is used for baseload, it's dispatchable.

Scheduling: I'm not sure the scheduling problem is worse for hydro than it is for LEO/MEO satellite swarms: to actually have baseload power, you need enough satellites that a ground station always has one in view. A GEO satellite at least stays in the same place, but see p.31 of the Boeing talk. Even a GEO is dark ~70 minutes/day some times during the year.

Pages 34-35 of the Boeing pitch are useful, ending with claim that time-averaged power per unit land area is best for space solar [and this may well be true], although the low/high estimates bracket the low-high estimates for ground solar. I don't know what their assumptions are.

p9. Jevons paradox
It is hard to reconcile:
a) The world will have much less energy
b) More efficiency means people will use more energy.

If people are up against the wall of declining energy availability, I'd suggest that Jevons is rather less applicable.

p21. "led by California's aggressive and failing RPS"
Shows numbers for 2003-2007. Yes, it is aggressive, and it is nontrivial to make this happen, and 20% by 2010 seems unlikely, but failing? That's pretty dismissive, especially since the addition of 2008 to the chart is interesting. Serious changes take time.

The Q1 2009 CPUC Report on RPS says

"New installed generating capacity more than doubled in 2008, to 870 MW of new capacity since the start of the RPS program
More than 500 MW of new RPS‐eligible generating capacity completed construction in 20081, representing 60% of total new capacity installed since 2003. This amount of new RPS capacity is more than four times what was added in any previous program year, 2003‐2007... Clearly, 2008 was a turning point for the RPS program and contracted projects are beginning to deliver in large numbers". Figure 2 shows the relevant chart.

p22. Wind power loss. Yes. Of course, unlike the rest of the Lower48, Texas has its own power grid. It's part of neither the Eastern or Western Interconnections. In any case, The Reuters article also says:

"System operators curtailed power to interruptible customers to shave 1,100 megawatts of demand within 10 minutes, ERCOT said. Interruptible customers are generally large industrial customers who are paid to reduce power use when emergencies occur.

No other customers lost power during the emergency, ERCOT said. Interruptible customers were restored in about 90 minutes and the emergency was over in three hours."

Those words are found right between the comments quoted on slide 22.

slide 48: "2006 world PV production was 2.1GW".

And was 3.4GW in 2007, then ~6GW in 2008. 2006 was rather constrained by silicon availability as people were frenziedly building new facilities.

slide 54. One would guess that PV technology could improve in two ways:
a) Space PV was same as terrestrial, so rides same learning curve.
b) Space and terrestrial have different optimizations. Until SSP is a substantial volume, vendors are likely to optimize for terrestrial.

(time to sleep).

Anyway, I think there are many interesting points to SSP ... but I worry about the pattern here. I understand advocacy, but when omissions mostly work one way (in areas I know), I worry.

This idea is even dumber than those lunatics talking about people having computers in their homes some day! I mean, really, everyone know that computers take a large specially built room with special air conditioning to handle the heat load from those thousands of vacuum tubes required to operate the computer. And they only operate for a very short time between failures of vacuum tubes limiting their usefulness. And the cost to power and replace those vacuum tubes would be prohibitive for anyone other than a large government. Additionally, those computers are hopelessly complex things that a simple homeowner could never manage to work with and take care of. Desktop computers are strictly science fiction and always will be.
And then there is that crazy President talking about going to the moon - in under a decade no less! No human being could ever survive in space and everyone knows it. Even if it was possible, and we have already agreed that it is impossible, it would take at least 50 to 100 years to accomplish. Nope, going to the moon is strictly science fiction and always will be.
Steam powered boats? Harrumph, strictly Fulton's folly!
Aluminum is to difficult to refine and will therefore always be used only for rare specialized uses. (look up the price when it was first produced)
Dick Tracey's wrist radio. Strictly science fiction.
Every technology we have today was at one time pooh - poohed by the naysayers of the time as never going to happen, to expensive, to difficult, etc ad naseum.

Oh, wait a minute, come to thing of it we did go to the moon in under 10 years, successfully, more than once. And you do have a desktop computer - connected to a science fiction level "Internet" and that desktop computer technology was dramatically accelerated by the "go to the moon" program.
People that are absolutely sure that something can never be accomplished will always work to make sure nothing is ever accomplished.
Look at the history of aviation. Very short time from first flight to scheduled airlines, another short jump to jet powered airlines. But there were plenty of naysayers all along the way.

I don't know if space power will happen, but we do have the capability to make it happen if we put our collective minds to the task. I would a lot rather see out government funds being spent on space power research than on funding the banksters to the tune of trillions of dollars. At least we might wind up with something of value in the end?

I am glad to see this article of another energy possibility here on The Oil Drum. My thanks to the author for taking the time to write and post it for those of us who are still open minded about the future.

Thanks for your comments! Good points. I am hoping Darel will be available to stop by later this afternoon.

Technical optimism isn't a new thing. The examples mentioned do not necessarily relate to whether of not the SSP can or will be built. We all know that smaller, more capable computer chips continue to appear, but we are still driving cars which achieve mg performance levels neat those of the 1980's and driving over bridges built decades ago.

For every success in technology, there are many failures. Jon Kutz mentions going to the Moon, which was done by the U.S. back in the 1960's, but how long has it been since man has set foot on the Moon? Remember when the Space Shuttle was first proposed as a system which would provide cheap and frequent access to orbit, yet, things haven't turned out that way, have they? Now, the shuttle is about to be retired and there is no replacement vehicle for manned flight that offers any thing like that level of crew comfort. Single Stage to Orbit (SSTO) space planes have been proposed, but none have been built and placed in orbit.

I think that the space program is looking for another excuse to continue with space flight, other than scientific missions. Man in space is probably a bad idea, since there will always be a large overhead in the form of life support systems needed to keep the humans alive. It's said that just the radiation exposure on a trip to Mars would likely kill the astronauts. And, would we be bringing those guys back, given that they would need to carry enough fuel for the return flight? A trip like that might only work with electric propulsion, but not a chemical rocket, another technology which is not yet proven, from what I know.

E. Swanson

Jon Kutz -

Your point is well taken, and I have actually used the same sort of arguments when trying to convince nay-sayers that this or that is not impossible.

Basically, there are certain people who will dump on anything new out temperament or out of force of habit regardless of the merits of the new thing. Likewise, there are certain people who will latch onto any new idea regardless of how obviously hare-brained it might be. It takes good judgement and some wisdom to successfully navigate between these two poles. One can only evaluate something based on currently available information and informed judgement, fully know that things can change.

For example, the US record company executive who in 1963 turned down a recording contract with a British group called the Beatles probably made the right decision if they indeed didn't sound very good at the time. At the other end of the spectrum, in the mid 1950s the US Air Force spent several billion dollars trying to develop an atomic plane, a concept which seems ridiculous today.

But one thing that is often overlooked by people making the argument such as you have expressed is that for every success, such as the airplane or the internet, there have been dozens of truly bad ideas which have proven to be technical and/or economic dead ends. Many people have been ruined following a new idea (including none other than Thomas Edison, who almost went broke trying to make a new iron ore extraction process work on an ore deposit in northwest New Jesey).

Even a casual perusal of magazines such Popular Mechanics and Mechanix Illustrated of the 1940s and 1950s will reveal all sorts of off-the-wall schemes that never had a prayer of getting anywhere and which today seem hopelessly quaint. Only a fraction of new ideas make the final cut.

As for me, I'm still waiting to take delivery of my atomic-powered personal commuter airplane that one early 1950s issue of Popular Mechanix predicted that I'd be flying by the 21st Century.

I don't know if space power will happen, but we do have the capability to make it happen if we put our collective minds to the task. I would a lot rather see out government funds being spent on space power research than on funding the banksters to the tune of trillions of dollars. At least we might wind up with something of value in the end?

Ya wanna harvest energy in space and return something of value to man? Space based mining/refining. Think of all your 'interesting' problems you get to solve.

1) Material science dealing with the heat/cold cycles, radiation et la.
2) AIs to run the machines
3) Energy capture/conversion (see 1)
4) Cheap/safe way of entering/leaving the gravity well.
5) Learn about our solar system as we rip it apart to feed the refining operation.

"Every technology we have today was at one time pooh - poohed by the naysayers of the time as never going to happen, to expensive, to difficult, etc ad naseum."

--And don't forget those terrible horseless carriages powered by (GULP!!!)
gasoline! That gasoline is so dangerous it will start enormous fires which will engulf entire cities. The whole planet will be burnt to the ground in a matter of days!

Cars were an obvious mistake.

Steam power - cheap energy surplus. Computers - massive cheap energy surplus. Internet - massive cheap energy surplus. Portable communication - massive cheap energy surplus. Moon landings - several people went six times on massive cheap energy surplus.

None of our technology creates energy. We have to harness an existing surplus.

This idea is even dumber than those lunatics talking about people having computers in their homes some day!

Thanks! The naysayers, the doomers, the anti-everything, lay-down-and-die crowd DO get exasperating at times. They're predictable. Always the same response--knee-jerk. I wonder why they bother, but figure it's because they like to rattle cages. Just ignore them.

Ah, it's so touching to see the faith in Science!

That's different to plain old science, which is just the study of things to figure out how they work; the believer in Science! has blind faith that it'll save us like a Messiah. "They'll figure something out," the believer says, meaning "the Lord will provide."

By which reasoning I should go ahead and leap off a cliff because I'll figure out how to fly before I hit the bottom. Maybe - but probably not.

When there existed only vac tube computers, or only transistors, it was entirely fair to say that there could never be a computer in every home. Once microchips had been invented it was different.

If we make a technological leap equivalent to that from vac tubes to transistors to microchips, and make it for launch vehicles, for PV generation, and for numerous other technical obstacles, then it'll be a fair comparison.

Until then, it's just "believe in Science!"

Actually, it's more of a belief in Engineering! since this isn't actually a science problem at all.

We know how to do everything necessary for space-based power, it's just a matter of engineering and funding.

And for the second of those reasons, I don't see it happening.

"this isn't actually a science problem at all.."

Well... I think that's half right..

Engineering (and financing) decides when it gets to go up.
Science reveals when it has to come back down.

Well, engineering is "half science" or more if you want to get pedantic about it, but my point (and I thought this was obvious but I guess not) is that we don't have to discover anything to make Space-based Solar possible. We know how to do it. It just isn't likely to be practical any time soon.

Once it gets up to GEO it's not coming back down any time soon without help.

Gawd, I wish more people who contribute to this site would read H. T. Odum before they waste everybody's time with things like this. Equip yourself with even a rudimentary understanding of the universal energy hierarchy and it quickly becomes painfully obvious that the amount of high transformity energy (eMergy) invested in the construction, installation and maintenance of a such a space station would greatly outweigh, by an order of magnitude if not more, the amount of diffuse low quality sunlight that it would collect.

Besides, we already have a giant space based solar collector. It's called the Earth. It even comes equipped with waste treatment, food production, and water purification systems that are self-regenerating and self-recycling, compliments of billions of years of frequent maintenance and design cycles that have built in error checking, otherwise known as evolution. Pretty neat, eh?

Although, the current occupants seem bent on constantly running the thing too hot by loading it way, WAY beyond spec. Not hard to see that won't have a happy ending, but I guess there's no accounting for user error.


My instinct is to snear at the idea, as pure sci-fiism, technophilia run riot. But, if they can prove the physics makes sense, we have to give them a fair hearing.

I'm questioning many of the touted advantages.

(1) Greater watts per area of PV. Clearly the space based solution has a afctor of two-plus advantage here. Without atmospheric interference any location of a (flat) earth surface would see sun 50% of the time. With atmospheric problems, scattering and clouds the factor becomes greater. Nevertheless concentrated PV is possible on the ground as well. One could make the case, that the degree of useable concentration depends upon cooling. I would argue that high performance cooling systems might be better maintained on the ground. Thus I find the argument that space based PV can make better usage of active PV area unconvincing. In any case for concentrated PV, cost of the active PV material no longer dominates the cost, the real metric is how much optics you get per unit cost. Currently proposed ground based CPV concentration levels are in the range of 500 to 2000 times concentration. This enables the use of high-tech ultra-high efficiency multi-junction cells (current efficiencies near 40%).

(2) No fuel, or pollution. Well we gotta get them lofted into orbit. Apart from the energy cost there are concerns about the ability of the upper atmosphere to absorb rocket exhaust on a large scale. If we discover that massive scaling up of launches would seriously damage the ozone layer, that could prove to be a show stopper.

(3) Co-locating, the ground recievers, and other uses, such as farming, sounds nice. Is there any danger to ground personnel. Presumably the energy is RF. In any case, at least some ground PV concepts allow the ground to be used for farming ranching as well. I would argue that in the arid and semi-arid climates for which such concepts would be most useful, that partial ground shading would be a benefit to agriculutural usage. See the concept from CoolEarthSolar, which suspends mylar-ballon type reflectors, and claims the potential for capital costs of well under a dollar per peak watt.

(4) Security concerns. Would the orbitting stations be vulnerable to deliberate attack? If so that could constitute a serious national security issue.

*This milk does not come from cows which have grazed beneath a rectenna.

Private companies such as PowerSat Corp. have proposed erecting large rectifying antennas in order to collect microwave energy that is beamed from orbiting power stations.

This has "bad idea" written all over it. Where do I begin?

1. Beams. As noted above, if the beam wanders, things get crispied up. Lawsuits follow, people get mad, project abandoned.
2. Expense. As noted above: as it is it costs thousands per kilo. You'd have to get the gear up there, then a bunch of people to put it together, unless it self assembles, which I find unlikely.
3. Space Junk. There's tons of crap flying around up there. The larger the device and the longer it's up there, the more likely it will collide with something like a paint chip, which, at several thousand kmph strikes with devastating force.
4. Risk. Oil goes away. Nukes go away. You are dependent on solar power. You get into an argument with another country, they say "f**k off" and fire a missile at your solar array. Boom. No electricity. Fire a few of them, and suddenly you are not only out of electricity, but have no power to fix the problem. Multijillion dollar system taken out by a multimillion dollar rocket.
5. Repair/replace. How one of these things can build and launch another one of itself is questionable.
6. Providing cheap energy sends us back to Jeavons. These things would just end up supplementing the terrestrial nuke and coal powered systems - solution becomes part of problem.

There are other objections, but I think these are sufficient to say "no thank you."

That is how I'm taking this proposal too. The complexities,the financial, engineering and fuel dependencies of maintaining this make Nuclear look SIMPLE..

I can't stop wondering what kind of energy density is in that beam that is slicing through all layers of atmosphere. Does it reflect when it tries to penetrate certain weather or atmospheric conditions?

What happens if you fly through it.. is it relative to sitting too close to your Color TV, Climbing a Cell Phone Tower, taking a hit from a radar dish?

I remain to be inspired to even a glimmer of interest in such a notion.

"Providing cheap energy sends us back to Jeavons."
By that reasoning there is no point in trying to replace coal with nuclear or any renewable energy sources; you are putting to much emphasis on Jervons paradox it is not a law set in cement, we can replace 3 BTU's of coal with one BTU of electricity, and who says it is going to be cheaper.

The hour is so late, I think we should concentrate on what works. Nuclear power, gas pipeline from Prudhoe Bay, Mackenzie line, deepwater GOM, resusitate the Mexico fields, and build refineries that process heavy crude.

And the next Republican candidate could have the slogan "drill and launch baby, drill and launch", that way they wouldn't have to do any unpleasant things about solving the oil and GHG crisis for another 4 years.

The hour is so late, I think we should concentrate on what works.

Do you have some veridical epistemological source for your "hour is late" view that you could somehow share with lesser mortals?

Though I somewhat agree that we should concentrate for now on local sources, like geothermal, I consider the "hour is late" view as nothing more than warmed over fundamentalist Christian fanaticism and hellfire and brimstone fearmongering.

I don't know what Veridical means.. but I would say that the hour is definitely late for the technologies that idontknow used in his/her example of what works.

I would say as well, that if you are concerned that PO is anywhere near us now, that the hour is likely very late for us to have any decent options set up to weather a real Oil Interruption, heaven forbid a permanent one.

Bikes, Trains, Solar Hot Water, Gardens. Those all work really well. We should have more of them.


Said the Grandfather to his hyperactive grandchild.. "Hey! Slow down, life is long!" .. and turning to his laggard grandchild.. "Hey! Get moving.. life is short!"

I read a book by Gerard O'Neil in the 1970s (when in high school) on this concept. He recognized the energy costs of launching all of that gear from Earth and proposed gathering the materials on the Moon (one-sixth the gravity and no aerodynamic drag), launching them to a space station, and manufacturing the panels there.

This has already been well-rebutted by commenters in time zones further east, but I agree it's delusional.

However, it may be brilliant as a financial scam. I've seen some wealthy people significantly invest in space-power projects. They think it'll make them rich while saving the earth. There is certainly money to be made, but it's in milking the gullibility of the energy/complexity illiterate.

It takes very little to announce such a plan. Some engineers, a few astronauts maybe for the board of directors, some keen-o drawings; I could do it and pay myself a high salary from initial investors, and so could many of the other posters here. Wouldn't even be illegal. Getting a contract with PG&E was marketing brilliance.

The "engineering only" school of thought seems to specialize in defining things which are not physically impossible as though this is the only really salient criterion. This allows one to simply ignore the fact that a given project is impossible economically & politically, from the point of view of failure modes and vulnerabilities, from the aggregate improbability of a series of improbable steps which all most go right in sequence, to marginal or dubious thermodynamic benefit.

Don't get me wrong, there's a lot of money to be made... well, redistributed... and it will be. But the valid economics of this plan are in the fundraising and not the energy generation.

It's a shame. It'd be cool if it were possible, but it isn't. I used to spend time with Gerard O'Neill and did my best to promote his ideas, have helped run a pro-space-exploration organization, have done a lot of tech innovation and involved astronauts and NASA folks in my projects. In other words, I'm not coming at this as a greenie luddite. It simply won't happen; and is more of a religious crutch than a feasible plan at this point.

To those who actually believe our current situation can segue seamlessly into a huge fleet of flawlessly robotizcized heavy-lift rockets for an uncertain and delayed payoff on investment, vaya con dios. To those seeking to invest, I've got some prime space on a dyson sphere you may be interested in...

However, it may be brilliant as a financial scam.

Wich irritates me since there litterally are hundreds of reasonable investment ideas that do something usefull for various resource scarcity problems.

I realy should learn how to turn ideas into businesses. *sigh*

Some might say that it is far more reasonable for these kinds of projects to work than it would be for us to all return to agrarian system.

Some say all manner of foolish things.

For what it's worth, I don't think we "all" will become agrarian, except in the sense of eventually being fertilizer. Maintaining 7+ billion humans is a short-term experiment.

There once seemed to be a chance for humans to exploit space industrially while preserving the earth as a biological preserve. But it was an illusion which didn't really take the nature of human behavior into account.

Regarding solar energy, I think the following is much more reliable:

Solar Systems to Build A$420 million, 154MW Solar Power Plant in Australia
27 October 2006
A A$420 million (US$321 million), 154MW solar power plant—designed to be the biggest and most efficient solar photovoltaic power station yet in the world—is to be built in north-west Victoria, Australia by Australian company Solar Systems. The Victorian power station will meet the annual needs of more than 45000 homes...

I think it is truer to say 'the Victorian power station will help meet the needs of 45,000 homes'. If cheap enough then concentrating PV without overnight energy storage will be great for helping power summertime aircons in distant Melbourne shopping malls and office blocks. The alternative is that houses and buildings use more passive cooling methods. Adding fixed non-concentrating PV with microstorage (=batteries) to each of those buildings makes it even better.

When CPV makes it possible to dynamite one of those lignite power stations in Victoria that will be real progress.

Cheers, Darel Preble
Chair, Space Solar Power Workshop
Psalms 19:4-5

Is a bible citation supposed to somehow make you more credible, likeable, seen as an authority figure?

Space based power showed up in an old drumbeat
And in that drumbeat SSPs got torn to shreads.

Actual SSP power plans

the solar collector would need to have an area of 10 km2, and would consist of either photovoltaic cells or solar thermal turbines. ..... The peak microwave power-flux density at the rectenna site would then be 300 W/m2,

Yet PV on land is

solar electric generation power density (global mean of 170 W/m²)

Now here is a graphic showing the size of PV on land to handle man's needs now.

The small black dots show the area of solar panels needed to generate all of the worlds energy using 8% eff. PVs.

And this link claims only 1/6 the power of solar radiation

As for potential health risks, Damphous insists that "by the time the beam has reached the surface, it has spread out considerably. The energy density is one-sixth that of the noon-day sun."

Oh and for 'global warming' arguments - beaming power from space to earth ADDS to the heat load of the planet. Don't see that addressed by Darel. Nor do I see the baseload point being addressed by humans instead of having what they are used to (instant on power) living with a model of 'make hay while the sun shines' - if the generation is happening, you use it. Claims like 'no personnel' or 'no CO2' are bogus as yes there are people and yes concrete is going to be used. But Darel - lets not focus on what you've claimed in your post - lets focus on the data from actual "research" - do refute the links and data I've outlined.

Show how the beamed power is not at a 2x or even 1/6 power level of present solar energy hitting the planet. Show how the graphic of little black dots is wrong.

By the way, I do know Darel, and he seems like a nice fellow. He also lives in the Atlanta metro area.

Then perhaps as a favor to you he'll refute the 1/6th to 2X power levels I've provided links for.

I do not ask for much.

Would the same investment in either money or energy be better used by investing in OTEC? OTEC is 24/7/365 since it uses the thermal energy that is stored in the tropical ocean. True baseload renewable energy. No need to lift anything 36,000 km above the Earth. The overall conversion efficiency isn't that bad when compared to the energy of putting all that mass up there. Some OTEC systems create desalinated water as a byproduct which many coastal desert communities would gladly pay for. OTEC brings nutrient rich deep water up to the surface to feed mariculture food systems.

No idea - But messing with the ocean has a few issues I can think of:
1) Messing with the ocean life
2) Warming the hydrates

Oh and for 'global warming' arguments - beaming power from space to earth ADDS to the heat load of the planet.

The math doesn't work for that counter argument. Current human power usage is about .01% of the planets solar input. The forcing due to greenhouse gases is around 1% -or a hundred times worse. Unless you believe that via Jevons paradox we will exponentially increase our demand for energy until we fry the planet that way. And occasionaly these things would shade the planet. If we could build stuff like this, we could probably build orbiting (or Lagrange point) solar shades. I'm also not worried about the beam getting lose and frying things. But I still think the idea is techno delusional. About as sensible as the people who want to mine
the moon for Helium 3 (to fuel fusion power plants, which we don't know how to build). They are trying to drum up support for the maintanence of an oversized space program.

The math doesn't work for that counter argument. Current human power usage is about .01% of the planets solar input.

If people are willing to change light bulbs and drive less under the worry about their CO2 contributions, why would they not oppose SSP for the same heating reasons?

(I'll note that Darel nor anyone else has offered up a rebuttal to the data I posted. I've spotted 2 other 'lets go to space for power' supporters and at least one 'the US military must own space/the high ground' supporters. So come on, show how the 2x conversion is wrong. Show actual numbers proving that the energy expended in creation, launching and operating a space based SSP makes more sense than a whole lotta PV on the ground.)

Sure, Eric -

Lets look at a large modern ground solar power plant, such as the Serpa solar power plant (a suntracker) completed in 2007 by many major players:
Serpa is an 11 megawatt facility and sits on a 60-hectare (150-acre) site. Now 1 Acre = 0.004047 Sq Km, that means we would get 356 Megawatts peak power with 32.35 Serpas tightly packed in a 5 kilometer diameter circle.
That 356 Megawatts is only available about 6 hours of an average day during the year if it’s not cloudy or rainy and the panels have been cleaned. To make that array baseload - assuming just one day of clouds next day - we must provide energy storage such as flywheel storage, as CAISO is now seriously considering, which would derate that 356 by a factor 9.6 to 37.083 MW. That means it could provide 37.083 MW for the two days from the 5 km diameter array.
Now imagone that 5 km diameter site loaded with SSP. This is baseload - it stays at 5 Gigawatts over night summer or winter through clouds or dust. It is is shadow for about 72 minutes at midnight during the equinoxes. Most importantly your refrigerator wouldn't miss it during that time. And the land underneath the rectenna can be farmed or ranched. Essentially SSP has no land cost since ~ 90 % of the light gets through the “chicken wire” rectenna. The Serpa land is a dead loss and must be amortized as purchased land. SSP provides 135 times as much power from that 5 km circle.
Intermittant sources like ground solar or wind are noncompetitors in the real world of electric power generation. Wind is best used for making liquid fuel, distilling water, etc., on site, for example, uses which don't require continuous duty. The solar charts you often see, like the black spots you mention are typically showing peak capacity, not actual annualized output on a dispatchable baseload basis. The cost of storage and transmission makes them uncompetitive for the real grid. Their marginal cost is too high.

The bible quote is a thread for another day, Eric. Meat and potatoes first.

it stays at 5 Gigawatts over night summer or winter through clouds or dust.

Must be magical microwaves - because the normal ones DO degrade with water vapor (clouds) and dust.

But do go ahead, show how microwaves are not effected by water vapor.

The Serpa land is a dead loss and must be amortized as purchased land.

From your own link:
the Serpa plant is on a 60-hectare (150-acre) hillside and is a model of clean power generation integrated with agriculture.

Integrated with agriculture...Serpa land is a dead loss....hrmmm whom to believe....Wikipedia or Darel?

Essentially SSP has no land cost since ~ 90 % of the light gets through the “chicken wire” rectenna.

You seem rather sure - so what exactly is the watts per square meter? At 135 times 170 watts per square meter the land under a rectenna strikes me as 'not useable land'.

Intermittant sources like ground solar or wind are noncompetitors in the real world of electric power generation.

Really? Because you say so? Is it a 'dead loss' like the land above?

I've got PV panels on the ground that do a fine job of generation of 'real' watts. Moving real 6 HP 48 DC motors. Moving real 2kW and 400 watt motors. Powering real 48VDC servers that store and process data.

The cost of storage and transmission makes them uncompetitive for the real grid. Their marginal cost is too high.

Got proof?

Now I asked for the data *I* presented of Watts per square meter to be shown as correct/incorrect. You make a claim of

SSP provides 135 times as much power from that 5 km circle.

Yet this does not match with the 300W/m2 or even the 1/6 the energy of sunlight claim. Show the 300W/m2 number is wrong.

Meat and potatoes first.

Is that meat government pork?

Yep. We know how to do it, we know it will work. Solar from the deserts, wind from the windy places. HVDC knitting it all together-- and quit the goddam WASTE of ENERGY. and there we have it. Pay for it? Stop doing stupid things like more and more cars and roads. Take that money, time, talent, materials and put it where it counts- solar, wind, HVDC.

And birth control. That most of all.

BTW, it seems to me that any proposal for future energy be compared with solar/wind/HVDC as a normalizing parameter. What's the ratio? First Question. Needs the first answer. That would put space power out of sight, right.

I'm not a big fan of PV in the desert either - I question the resources to move the captured energy and the changes to the ecosystem - but the watts to be captured at the earths surface doesn't make sense for the expense of SSP. A 2X gain? For the cost of moving materials outside the gravity well AND then maintaining that outside the gravity well EQ?

Then to make the counter claim of a 135X gain over 'standard PV' of 170W/m2 - doesn't pass the smell test.

And from the end of the pool Ron hates:

That link talks about alternative reasons for the announcement. Course it could also be bet hedging. The fun would be if the PG&E rate holders started a krefuffel that if PG&E has money to waste on such - they should reduce the rates charged.

A citation of the Psalms? For those of you keeping track at home, here are the verses cited:

Their voice [the heavens] goes out through all the earth,
and their words to the end of the world.
In them he has set a tent for the sun,
which comes out like a bridegroom leaving his chamber,
and, like a strong man, runs its course with joy.

I assume Darel means for SSP to be some kind of analog to the "tent for the sun" that God is depicted as having set in this Psalm? Is there no end to the hubris of man?

We need to adopt an ignorance-based worldview. A human project of this scale will always fail; it will always have unintended consequences.

How about instead of desperately building huge gigantic things and launching them into outer space, we ask ourselves: What is the ideal form of the human-energy relationship, and how can we move closer to it? Do we want to be more like flowers in our dealings with the sun, for example -- or more like Darth Vader (after he succumbed to the Dark Side, naturally).

This thing looks and feels like the Death Star.

Well state, O...

And isn't it interesting that those who would have us put all our eggs in one basket and gamble hundreds of billions, if not trillions of dollars on dreams of this nature, and against which dozens of well-founded objections have been stated, can't come out in support of developing the Atmospheric Vortex Engine (, for which ZERO science-based reasons to counter its workability have yet to be presented.

The cost of building a demonstration plant for this technology would only be in the $50 million range, and the ultimate deployment of each one would be independent of all else, allowing distribution on a local basis, giving a more secure and reliable system (no robots required for maintenance).

I guess that, just as in the case of telling lies, it's the REALLY BIG boondoggles that tend to capture the public's (and GE's) imagination.

Sorry about the type-O...

We need to adopt an ignorance-based worldview.

Nuff said right there to discredit the naysayers.

I appreciate this thread although it's been pitched to a skeptical crowd.

I doubt that this is going to make economic sense on a purely commercial level in our lifetime.

But US space policy is not based on purely commercial concerns. And while it hurts me to say so, I'd rather be blowing money on this project than on a manned mission to Mars.

There are many other ways to spend the money. For example, it might take about $2500 to install a solar hot water heating system on a house. Spending $10 Billion on solar water heating would equip some 4 million homes. If there's any prospect that the SSP will be a failure, I think it would be better to spend the money installing the solar hot water systems...

E. Swanson

Spending the money on solar water heaters does not help us build or maintain a military space based capability. There is a synergy between the civilian and military sides of US expenditures on space tech.

Just building the SSP would help encourage the training and employment of a couple hundred engineers many of who would work on military projects in the future. If successfully completed, the military could lease the power to extend its basing capabilities in Asia, Africa, and Latin America. I wonder if you could have a human-portable rectenna? And what a cool new capability to demonstrate our continued global power.

So I understand your proposal of 4 million solar hot water systems. I can even see the strategic value of increasing our domestic energy production. But this project is about extending military capability both into space and the rest of the globe. Nations rarely power down voluntarily. Hegemonic power has its own logic.

I don't see the need for a 'Space-based Military Capacity'.

A people should be able to defend themselves as necessary.. but this Imperial fantasy of owning the Heavens is so close to an Icarus Dream. We're still regularly trying to relearn how High Level Bombing rarely accomplishes what we set out for it to do. It crushes things, but it doesn't solve them. Hitler over London or US over Torabora..

These Predator Drones are making James Cameron look like a bloody Prophet! Skynet is practically a reality.. are those things even government owned, or did we shop them out? How many have we sold to Israel or India by now?

Happiness is a warm gun puppy.

From 'Trouble with Trillions'.. that fount of complete wisdom!

Agent Johnson: "We believe Burns still has that bill hidden somewhere in his house, but all we've ascertained from satellite photos is that it's not on the roof."

I don't see the need for a 'Space-based Military Capacity'.

The 1st step on the SSP boon-doggle is to get it labeled for what it is - a military program. Then one can debate its value as what it really is.

Because its value as a civilian power source is shown to be a bankrupt idea.

This chicken and egg situation could best be solved by chartering a Sunsat Corp with the deep pockets necessary to bridge this chasm.

Why not model this after NASA? This would, after all, be a national project, perhaps even a global project.

...providing the energy keystone for a favorable future global energy, environment and economy.

While a reasonable person would want to include a project like this among the mix of energy sources, why make such a system the keystone?

Geothermal energy is clean, free, and available 24 hours a day, so why isn't geothermal the most logical keystone? Why make the keystone a high-risk system?

Right now some of our best candidates to reduce fossil fuels in the mix are: nuclear fission, wind, geothermal, and concentrated solar. Some possibilities in the wings are some form of nuclear fusion, thorium based nuclear, etc. We are not going to eliminate oil and coal from the mix in the near future, but reduce its percentage. If we make 15% of our electricity from coal instead of 50% while powering down through efficiency and conservation, we will have a huge impact on climate change. If we reduce our consumption of gasoline and oil through development of mass transit, local fleets of electric vehicles, manufacture of fewer, more efficient internal combustion vehicles, we may be able to mitigate against peak oil. I have no objection to hearing about energy alternatives which may not be proven as long we devote energy and resources to likely candidates to reduce our vulnerability to peak oil.

You Americans have lost your gumption with your oil.
Oh well, we will have to leave it to the Asians.

The problem with the Space Based Power is that it is not too big but too small.
They are trying to sail too close to the wind.

This is what you should be aiming for.

An economist (whose name eludes me, but was in the Encyclopaedia Brittanica) started off to show that the moon would always be a lost cause. His views changed with the financial figures.

Sombody is going to claim LeGrange 1 and 2.
It is not you obviously.
Whoever controls the high frontier controlls the world.

Here is how you do it.
You get to the moon. This is the difficult part.
Costs can be offset by mining hydrogen isotopes.
Once on the moon a linear electric launch pad is built to launch material to L1 and 2.
Millions of tonnes are needed.

A space colony is established.
All sorts of things go wrong, just as they always have in new colonies.

The benifit of this is total domination of whatever is still valuable on the earth.
Other than that I can't think of anything.

"The benefit of this is total domination of whatever is still valuable on the earth."

How can people write sentences like this? It's just silly.. and more than a little disturbed. I hope you're joking. (I would love to make a movie about a 'Ringworld' like that.. but look what it takes just to make the ISS happen.

'Things go wrong..' yes they do.. and as such, some programs fall completely apart.. the faults aren't always repairable with even the most committed goodwill and abundance of outside energy and funding. Look at what it takes to keep a few little labs running in Antarctica.

I'm still hoping you're having me on..

but this is the songvirus you've given me. I could do worse..

And if the cloud bursts, thunder in your ear
You shout and no one seems to hear.
And if the band you're in starts playing different tunes
I'll see you on the dark side of the moon...

...All you create
All you destroy
All that you do
All that you say.
All that you eat
And everyone you meet
All that you slight
And everyone you fight.
All that is now
All that is gone
All that's to come
and everything under the sun is in tune
but the sun is eclipsed by the moon.

Ah! The Floyd. We agree on that point.

How about
Darkness at the break of noon
Shadows even the silver spoon
The home made blade, the childs balloon
Eclipse both the sun and moon
To understand you know too soon
There is no sense in trying.

I was goading thee into action.
The reason to become ourselves is that we are a part of Gaia and Gaia needs us to protect ourselves from the ever warming sun. We (Gaia) are unable to regulate our temperature by sequestering carbon anymore. Our atmosphere has only 4% carbon remaining. Further sequestration will not prevail.
Our desperate hope is to re-develop intelligence to protect us.
Agreed it is rash, but the alternative is to fry when the habitable zone migrates outwards.

If I recall, this idea was being seriously pursued by NASA few decades back. They had even formed an inernational team of renown engineers and scientists.
I think that the transmission of the Power from the Space energy city was to be by Laser beams. The critical problem to be resolved at that point was the issue of cost effective collection of solar energy and convert to Power.
I wonder what happened to that project.

The solar energy up there is not sitting in little contained boxes gift wrapped for anyone to use if they want. It is doing something. Has anyone tried to figure out what effect trapping a bunch of it and beaming it to earth would do to the current state of things in the atmosphere and on earth. Everything that is is part of how things are at present. Change it and you change how things are. We thought coal and oil were just taking up space under the ground. We have found out (perhaps too late) that they were serving the function of capturing carbon so that the atmosphere had less CO2.

It is HUBRIS to think that some other energy is just unused and can be tapped without consequences. Using solar, on the planet, in the atmosphere, using wind or tide for human purposes has never been done in a massive way. Are we really ready to once more try an experiment that may have consequences that are hugely negative and possibly irreversible? Is living a lifestyle that has only been available in the last hundred years of human existence worth the chance? Were all the lives of humans in the thousands of years before the industrial revolution not worth living? Are the lives of 3 billion humans who live on two dollars or less a day not worth living? Is the only life worth living one of huge energy expenditures? Couldn't we just say "well it was nice while it lasted and then power down to our great, great, great grandparents' lifestyles? Were their lives miserably unlivable and only worth sending on genes so we could have huge houses, air conditioning, cars, etc etc etc.?



Is living a lifestyle that has only been available in the last hundred years of human existence worth the chance?

Very definitely YES!

Were their lives miserably unlivable and only worth sending on genes so we could have huge houses, air conditioning, cars, etc etc etc.?

If you went back in time you would find that those people back then would be just as eager as the rest of the world is today to get to the USA to live the lifestyle we have.
The only reason that people lived like they did way back when was that was all they had at that time. They didn't do it because they thought it was so great.

Jon it is clear that you believe that a life with lots of energy and stuff is the only life worth living. However sometimes people don't realize that while they think their stuff makes them happy people with less may be much happier.

The Happiness survey shows that Nigeria, Mexico, Venezuela, El Salvador, and Puerto Rico rate highest in happiness. In fact it finds the desire for material goods to be a happiness suppressant Hmmm. Maybe you need to do some soul searching about what really matters. Especially about why your wants trump all other concerns. Not because it will change anything if you do so as far as the rest of the world goes but because it might make the crash more bearable for you. Do Read Dmitry Orlov - Reinventing Collapse. Find out why the most devastated people in the collapse of the Soviet Union were the men most strongly invested in life before the collapse.

"The survey is a worldwide investigation of sociocultural and political change //conducted about every four years by an international network of social scientists. It includes questions about how happy people are and how satisfied they are with their lives.

It showed that average happiness has remained virtually the same in industrialized countries since World War II, although incomes have risen.

The analysis of levels of happiness in more than 65 countries by the World Values Survey shows Nigeria has the highest percentage of happy people followed by Mexico, Venezuela, El Salvador and Puerto Rico, while Russia, Armenia and Romania have the fewest.

"New Zealand ranked 15 for overall satisfaction, the U.S. 16th, Australia 20th and Britain 24th -- though Australia beats the other three for day-to-day happiness," said New Scientist magazine, which published the results in this week's issue.

But different factors were said to make people happy for example , Personal success, self-expression, pride, and a high sense of self-esteem are important in the United States. In Japan, on the other hand, it comes from fulfilling the expectations of your family, meeting your social responsibilities, self-discipline, cooperation and friendliness.

The exception is Denmark, where people have become more satisfied with life over the last three decades. Researchers believe the unchanging trend is linked to consumerism.

Survey after survey has shown that the desire for material goods, which has increased hand in hand with average income, is a happiness suppressant."

2. SPS requires no fuel – zero pollution – and has no operations personnel. It is an antenna with green farms or ranches beneath the rectenna. SSP is the cleanest source of virtually unlimited baseload energy. Ground solar takes 100 times as much land usage to provide the same power as baseload SSP, similar to baseload power plants. Eventually Sunsat Corp could even provide much of its own fuel, through electromagnetic launch which even now has been developed as a first stage.

SPS requires no fuel? Is it built 100% from solar power? How do you get the bugger in to space in the first place?

SPS generates zero pollution? Pollution free fabrication of the solar cells, launch vehicle, creation and transport of the raw and semi finished materials. No humans motoring about to the rectanneas to replace the odd capacitor or transistor?

SPS has no operational people? SPS stations run forever without human intervention. Highly unlikely!

SSP is the cleanest source of virtually unlimited baseload energy? First, what makes unlimited electric power a good idea? Would that not encourage us to consumer more of other materials and continue to over populate? Second, anyone claiming unlimited power should brush up on their thermodynamics.

Bottom line, if it sounds like snake oil and smells like snake oil, well then it probably is snake oil.

'show me how my numbers are wrong.'

That requires accepting your premise which I for one do not.

100% fuel free
100% pollution free
100% human free
Unlimited baseline energy

That is not a valid premise so why bother with the details? Unless of course this SPS stuff is 100% free, which it is, right?

What a load of nonsense.
By the time the signal reached earth the path attenuation would mean that it would
not even warm your hand.

Even if it had a magic zero loss path the antenna stabillisation problem would be
much more severe than a communication system.

Why change the suns electromagnetic energy to another frequency when you already have
the energy arriving on earth.

Has someone gone stark raving mad ?