Improving Power in Rural China

Heading Out (Dave Summers) is currently visiting China...perhaps these ideas will give us some inspiration for ideas here as well.

Solar heating of a kettle (30 min to boiling)

Powering Rural China

One of the concerns of the Qinghai Administration deals with the large number of herders that remain wandering the hills, as their herds migrate across the landscape. Apart from the concerns over over-grazing that the now-larger herd/flock size is starting to impact grassland stability, they are also concerned with the provision of power and easier physical access to the herder dwellings, and he provision of social services.

Driving out to see the Liujia Gorge hydro-electric scheme and nature park we passed through a street that illustrated one of the first steps in helping that had been achieved. Outside virtually every residence on the sunny side of the street (and about four on the other) there was a solar cooker of the type shown at the top of the page. These are extremely popular even where there is electricity (which is not that expensive) but are even more popular with the herders, since this gives them a source of hot water and power for cooking, without needing access to electricity.

The second step in giving folk power has been the introduction of the solar water heaters. The designs are quite simple, a drum, and thin collector pipes, and they are currently being sold, at a price of around 6,000 – 7,000 yuan (6.7 to the dollar). This is in contrast with electric powered heaters that go in at around 1,000 yuan, but that have a power bill. Despite the differential we saw a fair few installed, though to be honest I think I would be stretching it to say we saw 5% of the homes in the villages we drove through using them.

Solar water heater (cost around $1,000 installed)

But if the herder mentality is to change there are other changes that must also be made, the first being affordable, simple and power independent houses. (Along the lines of the solar house competition on the Mall, though cheaper and less complex, and without the utility and car provisions. ) With stability in population there might be a possibility of using a grid, but the return would not justify the investment.

Most power in the state comes from hydro, they also supply five adjacent provinces, and the size of some it truly impressive. We did a tour around the nature park surrounding the Liujia Gorge hydro-electric plant, rising from 2,000 m at the crest of the dam, up to 3,000 m looking down on the lake as we were driven through the Kanbula nature park (by minibus and golf cart, and then back to minibus and boat).

The Liujia Gorge dam and lake

One additional sign of change, as we drove through the villages was the rapidly changing construction plan, going from mud brick to baked brick, with house after house being rebuilt with the more resistant baked brick. The bricks are it seems, being baked using coal as the power source, but that cost is small relative to the benefit of the new (to them) material.

This is still a land where farming is a major occupation, with couples out every day tending “their patch” and making sure it is properly watered and weeded. This gives a different mentality and cost structure over that which we commonly currently consider when asked for an opinion.

Heating Houses and Tents

Room in a Tu community

The Tu have a significant minority status in China, and in Xining City there is a community, which has at least three culture centers. These show off the way of life of the Tu, and this is a typical room within their gated community. The platform contains a small wood stove, and a conduit that carries hot gases through the bed of the bed, before exhausting it. As a result the ceramic box is quite warm, and the family can thus sit here and eat, and drink, and if they collapse – we’ll they’re on a bed to start with. The amount of wood required to keep the fire going and heat the ceramic is relatively small, and as I mentioned we saw Pollarded trees, and sheep stretching up to eat new leaves and branches. We sat in here for lunch, around the table, and I was initiated into the ceremony of the three cups. (I also can confirm that ear of yak is quite a pleasant delicacy). The design from the bed came from North East China where the Tu originated. They also had a small still going which produced the ethanol for the ceremony.

The construction illustrates how much benefit can come from an intelligence of need.

In contrast, Tibetan tents, which are of a heavy and dark construction so that they can soak up as much heat from the sun as possible, have a central wall, with a small fire built into it. This is usually fed by dried dung, of which there is a pile usually outside. Outside the cities this is quite a common dwelling for the herders (and workers on the pipeline) though the tents were made of different materials and colors (white being the dominant other).

Central heating structure for a Tibetan tent

This post is a combination of two recent posts from Dave's Bit Tooth Energy Blog.

Fired brick is a in many ways a superior building material to mud brick, but the small scale production of fired brick tends to be relatively energy inefficient and locally polluting. It's widespread adoption in the developing world is a move away from sustainability. In many ways, it is the lazy option, in that cheap energy is used to make a durable building material that is often over specified for the building it is used in.

It would be better to use intelligent building design and the minimum of building materials with high embedded energy to make buildings that are durable by design - but use less durable materials where they are not environmentally stressed. However, this comes down to education of local builders and the buildings often need more routine maintenance over their design lifetimes.

The Tibetan tents are the other extreme - very low embedded energy, quick to build or erect, but a major health hazard to the occupants. Minor improvements in the design can drastically improve the quality of life for the occupants.

The Tibetan tents are the other extreme - very low embedded energy, quick to build or erect, but a major health hazard to the occupants. Minor improvements in the design can drastically improve the quality of life for the occupants.

What's the health hazard? fumes?


The World Health Organisation (WHO) estimates that toxic emissions from cooking stoves are responsible for causing 1.6m premature deaths a year, half of them among children under five years old. In China 83m people will die from lung cancer and respiratory disease over the next 25 years, according to a recent report from Harvard University.

The coal fired brick may indeed not be sustainably produced,but the coal is going to be burnt anyway,and the energy derived therefrom mostly used to produce steel used in cars,or run electric lighting and so forth-not in sustainable activities.

I unhappily will never be able to travel to China,but being acquainted with the habits of poor but fairly self sufficient people here in the mountians of the American south,I would bet that those overengineered bricks are still in use hundreds of years from now if they are as good as the ones commonly used here.

Given the fact that the coal WILL be burnt,I can't immediately think of a better use of it.

I expect to see the solar stoves in common use here in the states in poorer communities within a few years.

As to the health hazards of fires in tents,it seems to be well established that smoke inhalation is a major source of health problems when people live in similar structures.One good friend of mine died of CO poisoning inside a modern house a a result of a leaky flue and a furnace located under a faily tightly sealed den.It seems unlike that a traditional yurt or other movable structure would be THAT airtight.

Whilst I to some extent agree with you, if the brick is then used with modern cement mortars, the result is not easily renewable, as the mortar is stronger than the brick, and it is hard to remove without destroying the bricks.

Also, small scale firing is often ineffectual as well as inefficient - If the bricks are over or under fired they have drastically reduced strength or durability. Developing world brick works rarely have the raw material , money or training to produce high quality bricks.

It is an area were sustainable development aid from the west would actually be valuable.

Indeed, modern airtight house designs do introduce their own health hazards. Low level emissions from petroleum based paints and furnishings, and radon gas from granite ground rocks are two important ones.

"Lego" concrete blocks:

  • Build in days, not weeks or months.
  • Simply lift them into place, no need for mortar, it isn't needed to hold them together because they'll stand dry. Perhaps a sealing membrane to seal joints.
  • The blocks are reusable. The more standardised they are the better. If you don't need the building or wall any more, just lift them into a new configuration.
  • Huge thermal mass.
  • When the hordes come howling, they're not going to get through 60cm of concrete.

"When the hordes come howling, they're not going to get through 60cm of concrete."

Nope, they will break down your door or window. ;)

In regard to the changes in design that you suggest there are a couple of points. In Beijing they are building back to traditional designs in the backstreets behind the large edifices that you see on the main streets - with the gated compounds. This also holds true out in the rural villages, where the use of the flat roofs (Qinghai is a very dry state) allows for a significant heat capture in the winter (and thus they wouldn't be excited about the "whitewash" recently advocated by the Secretary of Energy).

We talked a little about the transfer of technology for small scale solar houses along the lines of the DOE Competition and they (state government) seemed very interested in following up on that. Remember, however that in Qinghai they want to put the dwellings where it is not possible to run power (low demand, high cost) and where they may be transporting in the materials by yak. In those places servicing the solar equipment has (see Botswana) been a significant problem, although apparently solved in Bhutan using the "Barefoot University" approach.

Ralph: What minor design improvements to the tents do you recommend for improving occupants' quality of life?

It is important to differentiate between building technologies and cooking methods. In the case of tent structures, it is actually the fuel (dung is the least clean fuel per unit energy extracted) combined with the type of stove used that makes the situation so hazardous, rather than the building structure itself.

Building structures in this region are highly insulated against the cold winters, but this at the expense of worsened indoor air pollution. Health is threatened in many traditional lifestyles due to limited energy options for both cooking and heating.

The article mentions solar energy options for people in Qinghai. However, neither rural villagers nor nomads are able to employ these technologies. The solar water heaters are difficult to transport and often leak (with adobe roofs this causes many problems) or break during the frigid winters, with temperatures well below -20C. The solar cookers available (and pictured) weigh around 95kg. About 20% break en route to villages, and they are too heavy for use by nomads or those living in tents.

These are some of the many challenges to overcome while also incorporating traditional knowledge and cultural patterns to produce a locally-adapted solution. We've been working on and studying these issues, and we welcome any comments or suggestions you may offer:

If coal was used for rural electrification the emissions would be horrendous. Both India and China have a 'bottom billion'. If those 2 billion people each wanted to increase their average CO2 by 20 tonnes a year that's an extra 40 billion tonnes. Anthropogenic CO2 is currently 27 billion tonnes I believe. Of course coal would run out much sooner.

However it looks like in emissions terms the Western middle class is going to meet the Asian rural underclass somewhere in between. Perhaps a new global class will emerge which is frugal though online. It will have telecommunications but not necessarily reliable grid electricity. Instead of cars this class may own electric scooters charged by microgrids. A few buses and trucks will be powered by biogas. A big night out may be watching your neighbour's small screen LCD TV.

The mistake is to create the belief that the world's current rural poor can each have a car, 24/7 appliances and a supermarket based diet.

Why in the hell are solar water heaters $1000 in China but well over $5000 minimum in the US of A? Installation costs can't be that much, can they?

Um! While I'm not sure of all the details, firstly labor costs are much lower, but secondly they take the heater water and run it down pipes that go down the outside of the building and in through a hole in the wall.

This may not be that bad for a single dwelling, but where you have a host of these pipes coming down from the roof of an apartment complex it is quite ugly. So I image that there is a significant installation cost in the US that goes toward making it a bit more aesthetic.

I did, however, having looked at the construction, ask the same question but the other way on, namely why are they so much more expensive than electric heaters. The answer that I got was due to the monopoly on manufacture, which is done by companies from abroad (mainly I think Japan, but I am not sure of that) who have control of the process.

Since I wrote the piece I took the train from Xining City to Shanghai, and we saw that while solar water heaters were not that common in the villages of Qinghai, as we descended into Xi'an and beyond they become much more prevalent and were about 50% likely to be on the top of apartment complexes in the larger cities.

evacuated tube collector

may need other items

i feel flat plate is a better bang for your buck

You may 'feel' that, but a flat plate collector can't work in -40 F deg weather.

An evacuated tube rig can.

Also - the $1000 price is for a batch system. And that is close to what you can buy 'em for in the states the last time I looked at importing from China.

Have a look on ebay for panel costs. £300-£500 for evacuated tubes. £1500 for a complete diy kit. £3000 installed. So, yup.

Also rather than simply feeding your DHW tank, you might as well install a "Heat Bank" or "Heat Store" which can then feed heat to your central heating as well. Replumb your existing boiler to feed the heat store, plumb the radiators to use the heat store as a source. Add a wood burning stove as a source as well.

If you DIY, payback can be 3-5 years. Otherwise, 5-10.

Profit margins on solar water heaters are huge.

The US price for solar water heaters is "set" by the UK/American firms that make the evacuated vacuum tubes, and of course, installation labor is a considerable sum in addition at regular construction / plumbing contractor rates in the US.

Then there is the markup --- many of the importers of the lower cost Chinese product --- are making whopping margins well above shipping cost, duties, etc.

2 to 4X their cost FOB China is not uncommon.

Look at your regular run-on-the-mill Walmart item. If it cost $10, you can be reasonably sure that the Chinese manufacturer got paid not much more than $2.50 less freight and insurance.

That $20 pair of jeans was sourced from China for less than $5.

I don't know about the US of A Daxtatter, but here in BC Canada I am selling and installing them for around $1,500.00. Depending on location (roof, ground, etc) and configuration. ie. compact units like here: , evacuated solar tubes seperate from reservoir (with recirc pump) , system in combination with instant gas water heater (not for fifteen hundred bucks of course)
Just to say, they can come cheap. The ones I currently install are imported from China btw. manufactured by a company named THpower.

If you are selling it for USD $1,500, your cost to buy that in China is probably somewhere around USD $200, and USD $100 to ship it to North America in container sized quantities.

I did some evaluations of some of the units available in North America from China, and here are some of the issues:

- Chinese units are built to relatively low standards for plumbing / water pressure / insulation / long term durability.

In North American use, first, there cannot be one model that fits all, but models tailored to each of the different major markets with different climatic / weather / and other needs.

The Chinese units must be far better built and engineered. Simply put, in North America, it is "install and forget" whereas in China, it is cheap to send repairman to fix it --- even if that needs to be done 2 or 3 times a year.

Here are some obvious problems with the Chinese units --- they may not apply to all, but many I saw:

- Not engineered to withstand North American water pressures commonly encountered.

- Many Chinese units are in fact, not intended for pressurized water system use at all --- but water is pumped up at relatively low pressures to a rooftop cistern, and then dropped down apartments by gravity alone. This is typical of rural installations.

- Insufficient insulation to withstand freezing / thawing in the climate extremes found in many parts

- Poor quality of components --- ranging from Rubber Seals / Gaskets / Mounts that do not appear to be weather proof / sun proof for a reasonably long time (e.g. 10 years). The best example are the rubber mounts for the glass tubes --- the ones I saw will hardly last 2 or 3 years in the USA.

- Corrosion prone components that cannot withstand the normal North American weather, which can / may include exposure to road salt or salt spray from the ocean.

- Question of durability in areas of the country with "hard" water or "aggressive" water.

- Insufficient service / support / CREDIBLE long term assurance of parts availability, let alone Warranties.

Units made to North American specs and needs can be credibly built in China --- but it will have to be made for and marketed by a credible North American retailer with long term service, maintenance and support --- and not an upstart vendor that may fold in a year or two... when trouble with the units start.

The local guys who cut your grass around here "on the side"charge about one third what it costs to get the guys with business phones,insurance,and accurate tax returns.

I would also hazard a guess that the average Chinese is not burdened with a building or plumbing inspection for such a minor job,nor a "realtor" or banker prissily demanding exact conformance to somewhat arbitrary installation standards.

The costs of civilization can add up fast!

It will take the Chines a long time to build a welfare/bueracrat state comparable to ours-which is spartan compared to most of Europe.

You might be surprised at how inefficient your welfare is compared to Europe. For example, health treatment is usually covered for all from general taxes and does not stop when someone becomes unemployed. As a percentage of GDP the spend is far less than USA but covers pretty much everybody and life expectancy etc is broadly similar to the USA.

I guess less is spent on administration. The system varies from country to country within Europe and may be covered by various taxes of course to disguise/confuse these from the voteriat, e.g. in the UK part of the tax is called National Insurance and is supposed to cover health and pensions it is paid by both employees and employers at about 13%, in Belgium it is called ONSS and for employers is about 30%. Private insurance is also available.

I assume your local guys are using equipment that has been expensed to a company and are not paying any taxes on their income, thus increasing everyone elses taxes - the joys of a cash based business:-) What's that American saying don't tax me, don't tax you, tax the person behind the tree???

You are unfortunately correct in your comparison of our relative expenses and inefficiencies in regard to medical care.Europe is obviously way ahead in this respect,and in energy conservation too.Other aspects of the American versus European way of getting things done are mostly debateable imo.

But as regards the guys cutting grass "on the side" they are most assuredly not using thier employers equipment.These are VERY small business in this country with very few employees and the boss/owner generally knows exactly where every machine is 24 /7.

When the tax burden "straight up" is about 40 percent (around 6 percent state incone taxes,and 15 percent FICA,and twenty plus federal incime,plus local taxes,plus avioded expenses such as the bookkeeper and the business phone and a properly zoned address from which to run a "legit" business,it's no problem to pay out anywhere from a couple of thousand to ten thousand or so to get a "one horse" operation equipped and running.
Some savings are not obvious at first glance ,such a a zero advertisng budget,and zero time spent on banking chores-get paid in cash,spend cash,do your own maintainence,etc.There is no supervisor,no insider theft,no sleeping on company time,no incentive to do any busy work or ass cover work etc.

All these guys really need is one good large mower,a push mower,a couple of trimmers,and a trailer,as in most cases they already own a pickup truck,which is also frequently used as the family car and commuter vehicle.In a lot of cases they use the same mower and other tools as they use to maintain thier own residences.

The most expensive AND inefficient workers worldwide I have ever encountered were in the USA, Atlanta. This was for an exhibition and I have done these all round the world, States, Europe and Asia. Everything had to be done by unionised labour which in fact meant they stood and watched my guys do the work, they had to transport stuff 100m from the loading bays at huge charge, basic stuff wasn't done e.g. no electric supply!!, stuff I had ordered months before wasn't delivered on time... My experience was typical of many others at the show:-(

This was for an exhibition

Ahh, yes. Trade show labor rates.

They have a captive group demanding their labor. A group that, as a whole, will throw money at a problem.

Ever seen the food costs at a trade show?

Please fix the following minor technical errors:

China's currency is the Yuan, or Renminbi.

Yen is Japan's currency.

The solar heaters work pretty well in rural areas where the line from the tank to the house is short --- and where the climate permits water to be warmed to lurkwarm (beats the heck out of cold water for baths).

However, it is not very effective in any high rise building except for the top floor.

The photos above do not show it well, but one big issue is that air pollution in many parts of the country has virtually eliminated bright sunshine on most days --- the sun being partially obscured by a haze that drastically reduce sunlight reaching ground level.

That is not only affecting the possibilities for solar energy, but also harming agricultural productivity.

Furthermore, drought, both from climate change and man made activities (like goat herding) tend to tear up sod and soils in the Mongolian plains, causing dust storms and more particulate pollution, and less sunshine.

The solar heaters work pretty well in rural areas where the line from the tank to the house is short --- and where the climate permits water to be warmed to lurkwarm (beats the heck out of cold water for baths).

The evacuated tube panels shown are better than 80% efficient. Can easily raise water temperature above 50C even in the UK under cloud cover. Bright sunshine is not required.

My 2 x20 vacuum tubes raised my 210 litre tank from 24 to 66 degrees at the base today. Top of the tank was about 71.

Fahrenheit or Celcius? If Fahrenheit it's terrible. Celcius, it sounds good enough for a good hot shower, a washing machine, dish washer and a bit more, but perhaps not enough for most central heating on it's own.

210kg by 42C is 37MJ. Assuming 16h of daylight, about 640 Watts on average.

What area do the tubes cover?

Have you thought of upgrading to say a 1000l heat store and plumbing both your existing heating and the tubes into it?

Fahrenheit or Celcius? If Fahrenheit it's terrible.

If it's Fahrenheit, it's terribly difficult to get the supercooled (24 degree) ice through the pipes :)

It's only -4, and the thermal panels I've come across contain antifreeze for exactly this reason, and he could be in the winter zone.

Almost Everyone Has a Solar Water Heater In Dezhou, China

How much heat is lost from the downpipe run into the home?

If that length is short, it is one thing, if that length is long.... it is a non starter for solar.

Many of the Chinese installations on rooftops seen in China are actually not full blown water heaters.

Their job is to warm the water to lurkwarm (its temperature by the time it runs down 3 or more stories), but a LOT warmer than water out of the tap from the ground.

Thereafter, if it is needed, in wealthier households, another heater (gas, electric, etc.) heats the water to the higher temperatures needed (or not needed).

However, for many poor households, even the addition of lurkwarm water (especially in the winter in many places without even space heating) is a big step upwards.

Imagine baths with water that is lurkwarm vs. just above freezing, or being able to wash clothes / dishes in warm vs. cold water. In the past, such hot water needs would have to be met by boiling pots of water.

Oops! Thanks for catching the error with the currency, which I have corrected.

We probably saw more of the heaters on high rises rather than single dwellings as we came down from the mountains. (But then that is where most of the population in the cities live).

The haze appeared at around 6:30 am as we travelled by train to Shanghai from Xi'an. Prior to that, and all the way down the valley from Xining the air was clear, and, until Xi'an, pleasantly cool.

The worry about overgrazing, whether by goat, sheep or yak is a significant worry, and is (so I was told) one of the contentious issues in Tibet, where the government want to rest and restore some of the pastures, right where the herders have traditionally migrated their flocks. We could clearly see the damage when we stopped along the road on the drive over to the Yellow River.

Overgrazing might be a problem, but remember that the Tibetans have lived sustainably in this harsh environment for millenia. When you dig a bit deeper, a lot of the problem that the Chinese government blames on the locals are actually created by the Chinese themselves.

My brother was studying cranes in Tibet and was frustrated when he saw herders scare the cranes away when they saw him coming. Later he realized that he was using the local Chinese conservation officials car at the time and the herder thought that was who was coming. When he had dinner at the official's house a few days later, the "chicken" tasted funny to him (even by Chinese standards). He wandered behind the house later and found crane feathers and other signs that a crane had just been prepared for the pot.

The Tibetans are by no means perfect, but in general they have deep cultural and religious traditions to respect and protect the local flora and fauna. The recently arrived Han Chinese have no such traditions of reverence toward things Tibetan--just the opposite.

"affordable, simple and power independent houses. (Along the lines of the solar house competition on the Mall, though cheaper and less complex, and without the utility and car provisions."

Like the solar decathlon I am trying for a cheaper and less complex 800 sq ft dwelling. which I feel is needed in all countries.

the Idea was to build a structure that could be constructed by one person with locally available materials (hauled with pickup or trailer).

Local lumber yards allowed. but no concrete trucks , hand mixed concrete if needed ,

I felt a recycled metal frame would be the starting point

Now ... how to infill the walls ? adobe plaster? foam, OSB, canvas tent sides ?

I have spent some time in China over the last few years. In an area I have spent alot of time, there are many small mom and pops brick yards (Not the Indy Brick yard). I could be wrong, but it appears alot of the bricks produced are used locally. The small operations might be more polluting, but not as bad as if there was a giant brick yard shipping brick loads 100's or 1,000's of miles. To an extent, it is the dream of many ecoenvironmentalists. Locally grown (or made) locally used. However, I am not going to get into the labor standards involved or wages of those workers. That in itself is an encyclopedia.

I bet that tea kettle in the first picture would start to boil a lot faster than 30 minutes if it's bottom were a dull black instead of an apparently somewhat shiny aluminum. After all, a solar heater of this type depends almost entirely on radiant heat transfer, and you don't want a large portion of the incoming radiation to be reflected back. What would also help is to have some sort of insulating cover over the top of the tea kettle to better retain the heat that is absorbed.

It's minor details like this that are very important when dealing with alternative energy.

Anyway, it's nice to see some real grass-roots stuff like this.

So are there any funds in the Obama Plan for say ..

The American Solar Corps to build and install solar hot water heaters and solar ovens ?

Any program in China ? Israel ??

Emissivity of aluminium. 4% polished. 20% if dull
Copper II oxide 90%
Carbon black 85-90%

So potentially a 5-20 fold increase in performance. Basically someone needs to sell "solar kettles" with the properties you describe, along with solar cookers.

I checked the short video section that I shot of the street as we drove up it, and all the kettles seemed to be polished (I counted 8 in the short length of street I recorded). This could be local housewifely pride in keeping up with those next door, but it could be a marketing opportunity for someone.

Or it could be that 15 min to boil vs 30 min to boil is not important.


These kettles only boil a few liters of water at a time and many more are needed for making soups for the 5-6 person family, or for giving to yaks or cows for increased milk production. In addition, not every day is maximally sunny, meaning that 1/2 time increase in speed could allow water to be boiled on a cloudy day.

At most homes, old, black kettles are used on the solar cooker; people know the advantages of the darker bottom. Guests are provided with newer, shiny kettles as they appear more presentable. A plastic bag to surround the kettle and prevent convection would also increase heat loss, however, this type of plastic bag is not readily available.

During the fall of 2006 I spent three weeks in China with some bridge players, more in the cities than the rural areas. The people were extremely nice. From a standpoint of energy I was impressed by the constant parade of coal barges on the Yangtze and the pollution, especially in Xian and Chongqing. In Xian even some of the locals were wearing masks. Driving through the countryside near Xian we were told that some farmers were illegally burning fields thus contributing to the pollution. Chongqing was so polluted that the morning we arrived the sun looked like the moon. It was hot. Many of the more than 30 million inhabitants lived in high rise apartment buildings with visible window air conditioning units. The popular automobiles were generally larger than one might see in Europe. The terrain was too hilly for bicycles. They were in the early stages of building a light rail system.
--- Was also impressed with the new modern airports and the ability of the pilots to land in the thick smog.