Peak Phosphorus
Posted by Prof. Goose on August 17, 2007 - 10:00am
This is a guest post by Patrick Déry and Bart Anderson. Patrick Déry is a physicist, energy, agriculture and environment analyst and consultant in Quebec, Canada. Bart Anderson is a former reporter, teacher and technical writer; he currently is co-editor of Energy Bulletin.
Peak oil has made us aware that many of the resources on which civilization depends are limited.
M. King Hubbert, a geophysicist for Shell Oil, found that oil production over time followed a curve that was roughly bell-shaped. He correctly predicted that oil production in the lower 48 states would peak in 1970. Other analysts following Hubbert's methods are predicting a peak in oil production early this century.
The depletion analysis pioneered by Hubbert can be applied to other non-renewable resources. Analysts have looked at peak production for resouces such as natural gas, coal and uranium.
In this paper, Patrick Déry applies Hubbert's methods to a very special non-renewable resource - phosphorus - a nutrient essential for agriculture.
In the literature, estimates before we "run out" of phosphorus range from 50 to 130 years. This date is conveniently far enough in the future so that immediate action does not seem necessary. However, as we know from peak oil analysis, trouble begins not when we "run out" of a resource, but when production peaks. From that point onward, the resource becomes more difficult to extract and more expensive.
Physicist Déry applied the technique of Hubbert Linearization to data available from the United States Geological Survey (USGS)[1] to phosphorus production in the following:
He tested Hubbert Linearization first on data from Nauru to see whether he could have predicted the year of its peak phosphate production in 1973. Satisfied with the results, he applied the method to United States and the world. He estimates that U.S. peak phosphorus occurred in 1988 and for the world in 1989.
Phosphorus (chemical symbol P) is an element necessary for life. Because phosphorus is highly reactive, it does not naturally occur as a free element, but is instead bound up in phosphates. Phosphates typically occur in inorganic rocks.
As farmers and gardeners know, phosphorus is one of the three major nutrients required for plant growth: nitrogen (N), phosphorus (P) and potassium (K). Fertilizers are labelled for the amount of N-P-K they contain (for example 10-10-10).
Most phosphorus is obtained from mining phosphate rock. Crude phosphate is now used in organic farming, whereas chemically treated forms such as superphosphate, triple superphosphate, or ammonium phosphates are used in non-organic farming.
Philip H. Abelson writes in Science:
More information:
In his frightening book Eating Fossil Fuels [3], Dale Allen Pfeiffer shows that conventional agriculture is as oil-addicted as the rest of society. A decline in oil production raises questions about how we will feed ourselves.
In the same way, agriculture is addicted to mined phosphates and would be threatened by a peak in phosphate production. As the U.S. Geological Survey (USGS) wrote in summary on phosphates (PDF):
Tools that have been used for analyzing peak oil can be applied to phosphate production. As we will see, phosphorus production follows a more-or-less bell-shaped (parabolic) curve, just as oil production does.
Hubbert's parabolic curve is based on a differential equation explained by Stuart Staniford:
Hubbert Linearization was first developed by geologist Kenneth Deffeyes, an associate of M. King Hubbert. The technique has been discussed by analysts such as Stuart Staniford, Jeffrey J. Brown and Robert Rapier at The Oil Drum. The term Hubbert Linearization was coined by Stuart Staniford.
In Hubert Linearization, the production data from the bell-shaped Hubbert curve is plotted as a line. On the graph:
This paper purposely minimizes the math so as to reach a wide audience; however, much more detail on H-L is available online. For example:
For the purposes of this paper, Déry looked at data for commercial phosphate (26-34% of P2O5). Other reserves of rock phosphate with lower concentrations of P2O5 do exist, but, just as with tar sand for oil production, they are more costly to exploit - economically, energetically and environmentally.
Using data from United States Geological Survey (rock phosphate production historical data series), Déry did a Hubbert Linearization for United States and for world rock phosphate production.
Results were stunning. The theoretical logistic curve fits almost perfectly with the real data curve. Déry found that we have already passed the phosphate peak for the United States (1988) and for the world (1989).
However those results seemed too perfect, so Déry tested the method on an almost depleted region of rock phosphate production, a case similar to that of United Stated for oil. A small island in the South Pacific called Nauru appeared to be an ideal case. The Nauru Island is 21 km² with only one economic resource (besides being a fiscal paradise!): rock phosphate. This resource has been almost entirely depleted since 2005.
According to the CIA World Factbook:
Plotting the rise and fall of rock phosphate production on Nauru yields this graph:
To begin with, Déry made a Hubbert Linearization with the stabilised data (linear trends since 1959) and found an Ultimate Recovery Reserves (URR) equivalent of 77 000 kT and a peak of rock phosphate production in 1973.
Looking at the results, he asked himself a question: would it be possible to predict the URR and the profile of future production just before the peak or just after? To get an answer, he used the data from 1959 to 1970 (just before peak) and 1959 to 1980 (just after peak). The results were :
If we calculate to obtain production curves for all these scenarios and put them on the same graph with real data, we obtain:
We see that the Hubbert Linearization just before peak, with this data set, exaggerated the URR (+26%) but the peak date (1978) was not so different from the real peak date (1973). It’s the contrary for a H-L just after peak: the URR is slightly smaller (-6,5%) and the peak date is earlier (1971).
The case of the United States is worth investigating since it is the "world’s leading consumer, producer, and supplier of phosphate fertilizers," according to the USGS.
Plotting phosphate production for the United States, we obtain:
Using data from 1982 to 2004, we find an URR of 2850 MT.
Calculating the production curve and plotting them with the real data gives us an estimated peak of 1988.
Plotting phosphate production for the world as a whole we obtain:
Using data from 1968 to 2005 reveals an URR of 8000 MT for the world as whole.
Calculating the production curve and plotting them with the real data:
We can see from the preceding graph that we are probably on a world decline of rock phosphate production.
Conventional agriculture uses vast amounts of oil and gas to produce food. We have just to plot data of world population versus world oil production to see the strong correlation between them.
But oil production is not the whole story. Nutrients like nitrogen and phosphorus were also required for the “Green Revolution”.
Nitrogen is present in large quantity in the atmosphere (78% of its composition). The Haber-Bosch process for obtaining nitrogen uses one percent of all energy consumed by humans [5]. Nitrogen can also be fixed in the soil using micro-organisms such as rhizobium and azotobacters. If there is sufficient energy, nitrogen will be available.
Phosphorus may be the real bottleneck of agriculture. [6]
Population growth was only possible because we found phosphorus deposits and cheap energy to extract, transform and transport it to farms. When we plot data of world population versus world phosphate production, we find a significant correlation.
What does this correlation mean? Even if we find a real substitute for fossil fuels, it will be impossible to maintain population growth because phosphate deposits are probably in decline. It will be impossible to maintain an agriculture without recycling nutrients.
In some ways, the problem of peak phosphorus is more difficult than peak oil. Energy sources other than oil are available, though they all have their own shortcomings. In addition, the sun provides a steady input of energy.
Unlike fossil fuels, phosphorus can be recycled. However if we waste phosphorus, we cannot replace it by any other source. Currently we are running through the limited supplies of concentrated phosphates. Phosphate fertilizer is often applied carelessly, leading to waste and pollution. Food from agriculture goes to consumers and animals, who excrete most of the phosphorus. The phosphorus in sewage mainly goes to sea or is otherwise dispersed.
The key response to a phosphorus peak is to re-create a cycle of nutrients. F.H. King in his classic Farmers of Forty Centuries: Organic Farming in China, Korea and Japan [4] describes how returning human and animal manure to the soil enabled Asian agriculture to continue to be productive for millenia.
Sewage sludge is one method now used for returning nutrients to agriculture, although there are safety concerns about the process. Other possibilities include:
(1) United States Geological Survey (USGS). Phosphate Rock Statistics and Information. Last updated 2007. Multiple documents.
(2) Abelson, Philip H. "A Potential Phosphate Crisis." Science. 26 March 1999: Vol. 283. no. 5410, p. 2015.
(3) Pfeiffer, D.A. Eating fossil fuels, oil, food and the coming crisis in agriculture, New Society Publisher, 2006.
(4) F.H. King. Farmers of Forty Centuries: Organic Farming in China, Korea and Japan , Dover Publications, NY, 1911 (ed. 2004)
(5) Smith, Barry E. “Nitrogenase Reveals Its Inner Secrets”, Science, 6 September 2002: Vol. 297. no. 5587, pp. 1654 – 1655, www.sciencemag.org/cgi/content/full/297/5587/1654
(6) Conrad, Jim. “A bottleneck in nature”, Backyard Nature, www.backyardnature.net/phosphor.htm
(7) Jenkins, J.C. The Humanure Handbook, Jenkins Publishing, 1994
(8) Anderson, Joe. "Toilets vs. Life as We Know It." Energy Bulletin. September 2004.
(9) EcoSanRes (Stockholm Envrionment Institute). Closing the Loop on Phosphorus (PDF). April 2005.
(10) McInerney, Su. "A blooming waste," University of Technology Sydney (Marketing and Communication Unit). November/December 2006. [Short article about phosphate researcher Dana Cordell; see following entry].
(11) Cordell, Dana. Urine Diversion and Reuse in Australia: A homeless paradigm or sustainable solution for the future? (Master's Thesis). Department of Water & Environmental Studies, Linköping University. (PDF version.) February 2006.
Déry, Patrick, « Pérenniser l’agriculture » Mémoire pour la Commission sur l’avenir de l’agriculture du Québec, avril 2007, www.caaaq.gouv.qc.ca/userfiles/File/MEMOIRE(1)/02-07-Saguenay-Dery,Patrick.pdf (in french only)
Brown, A. Duncan. Feed or Feedback: Agriculture, Population Dynamics and the State of the Planet, International Books, 2003.
Gunther, Folke. Vulnerability in Agriculture: Energy Use, Structure and Energy Futures, presented at the INES conference, THK, Stockholm, 2000.
B.Gumbo, H.H.G. Savenije and P.Kelderman. 2002. Ecologising Societal Metabolism: the Case of Phosphorus. In: Proc 3rd Int Conf Environmental Management. 27-30 August 2002.
Steen, P. 1998, Phosphorus Availability in the 21st Century: Management of a Non Renewable Resource. Phosphorus and Potassium.
~~~~~~~~~~~~~~~ Editorial Notes ~~~~~~~~~~~~~~~~~~~
Patrick Déry is a "physicist, energy, agriculture and environment analyst and consultant in Quebec, Canada."
Bart Anderson is a former reporter, teacher and technical writer. He currently is co-editor of Energy Bulletin.
Patrick sent the original article to Energy Bulletin in April. I had never seen anyone apply the concepts of peak and Hubbert Linearization to phosphorus. Even though I had known intellectually that phosphorus supplies were limited, it wasn't until I read Patrick's paper that I realized how urgent the situation is.
To make Patrick's ideas more widely accessible, I added background information and did some wordsmithing, but all the original ideas are his.
For more background, see Peak phosphorus: readings (Energy Bulletin).
-BA
Physicist Déry applied the technique of Hubbert Linearization to data available from the United States Geological Survey (USGS)[1] to phosphorus production in the following:
- The small Pacific island nation of Nauru, a former phosphate exporter.
- The United States, a major phosphate producer.
- The world.
He tested Hubbert Linearization first on data from Nauru to see whether he could have predicted the year of its peak phosphate production in 1973. Satisfied with the results, he applied the method to United States and the world. He estimates that U.S. peak phosphorus occurred in 1988 and for the world in 1989.
Phosphorus - its role and nature
Phosphorus (chemical symbol P) is an element necessary for life. Because phosphorus is highly reactive, it does not naturally occur as a free element, but is instead bound up in phosphates. Phosphates typically occur in inorganic rocks.
As farmers and gardeners know, phosphorus is one of the three major nutrients required for plant growth: nitrogen (N), phosphorus (P) and potassium (K). Fertilizers are labelled for the amount of N-P-K they contain (for example 10-10-10).
Most phosphorus is obtained from mining phosphate rock. Crude phosphate is now used in organic farming, whereas chemically treated forms such as superphosphate, triple superphosphate, or ammonium phosphates are used in non-organic farming.
Philip H. Abelson writes in Science:
The current major use of phosphate is in fertilizers. Growing crops remove it and other nutrients from the soil... Most of the world's farms do not have or do not receive adequate amounts of phosphate. Feeding the world's increasing population will accelerate the rate of depletion of phosphate reserves.and
...resources are limited, and phosphate is being dissipated. Future generations ultimately will face problems in obtaining enough to exist.It is sobering to note that phosphorus is often a limiting nutrient in natural ecosystems. That is, the supply of available phosphorus limits the size of the population possible in those ecosystems.
More information:
- Understanding Phosphorus and its Use in Agriculture from the European Fertilizer Manufacturers Association.
- Phosphate Primer by Florida Institute of Phosphate Research.
Prospect of a Phosphorus Peak
In his frightening book Eating Fossil Fuels [3], Dale Allen Pfeiffer shows that conventional agriculture is as oil-addicted as the rest of society. A decline in oil production raises questions about how we will feed ourselves.
In the same way, agriculture is addicted to mined phosphates and would be threatened by a peak in phosphate production. As the U.S. Geological Survey (USGS) wrote in summary on phosphates (PDF):
There are no substitutes for phosphorus in agriculture.Fortunately, phosphorus - unlike oil - can be recycled. Responses to a phosphorus peak include re-creating a cycle of nutrients, for example, returning animal (including human) manure to cultivated soil as Asian people have done in the not-so-distant past [4].
Hubbert Linearization
Tools that have been used for analyzing peak oil can be applied to phosphate production. As we will see, phosphorus production follows a more-or-less bell-shaped (parabolic) curve, just as oil production does.
Hubbert's parabolic curve is based on a differential equation explained by Stuart Staniford:
The idea behind the equation is that early on, the oil industry grows exponentially - the annual increase in production is proportional to the total amount of knowledge of resources, oil field equipment, and skilled personnel, all of which are proportional to the size of the industry. ...To estimate future production and total production, some analysists have turned to the technique of Hubbert Linearization (H-L).
Later, however, the system begins to run into the finiteness of the resource - it gets harder and harder to get the last oil from the bottom of the depressurized fields, two miles down in the ocean, etc, etc.
Hubbert Linearization was first developed by geologist Kenneth Deffeyes, an associate of M. King Hubbert. The technique has been discussed by analysts such as Stuart Staniford, Jeffrey J. Brown and Robert Rapier at The Oil Drum. The term Hubbert Linearization was coined by Stuart Staniford.
In Hubert Linearization, the production data from the bell-shaped Hubbert curve is plotted as a line. On the graph:
the y-axis (vertical) is P/Q whereBy extending the line in the graph, one can estimate Ultimate Recoverable Reserves (URR) for the region (Qt).
P = annual production and
Q = total production to date
the x-axis (horizontal) is Q (total production to date).
This paper purposely minimizes the math so as to reach a wide audience; however, much more detail on H-L is available online. For example:
Hubbert Linearization (Wikipedia)
In Defense of the Hubbert Linearization Method
Another Way of Looking at CERA by Stuart Staniford
When Does Hubbert Linearization Work? by Stuart Staniford
Predicting the Past: The Hubbert Linearization by Robert Rapier (H-L skeptic)
Applying Hubbert Linearization to Phosphates
For the purposes of this paper, Déry looked at data for commercial phosphate (26-34% of P2O5). Other reserves of rock phosphate with lower concentrations of P2O5 do exist, but, just as with tar sand for oil production, they are more costly to exploit - economically, energetically and environmentally.
Using data from United States Geological Survey (rock phosphate production historical data series), Déry did a Hubbert Linearization for United States and for world rock phosphate production.
Results were stunning. The theoretical logistic curve fits almost perfectly with the real data curve. Déry found that we have already passed the phosphate peak for the United States (1988) and for the world (1989).
Nauru
However those results seemed too perfect, so Déry tested the method on an almost depleted region of rock phosphate production, a case similar to that of United Stated for oil. A small island in the South Pacific called Nauru appeared to be an ideal case. The Nauru Island is 21 km² with only one economic resource (besides being a fiscal paradise!): rock phosphate. This resource has been almost entirely depleted since 2005.
According to the CIA World Factbook:
...intensive phosphate mining during the past 90 years - mainly by a UK, Australia, and NZ consortium - has left the central 90% of Nauru a wasteland and threatens limited remaining land resources
Plotting the rise and fall of rock phosphate production on Nauru yields this graph:
To begin with, Déry made a Hubbert Linearization with the stabilised data (linear trends since 1959) and found an Ultimate Recovery Reserves (URR) equivalent of 77 000 kT and a peak of rock phosphate production in 1973.
Looking at the results, he asked himself a question: would it be possible to predict the URR and the profile of future production just before the peak or just after? To get an answer, he used the data from 1959 to 1970 (just before peak) and 1959 to 1980 (just after peak). The results were :
- Just before peak : URR = 97 000 kT; peak date: 1978
- Just after the peak : URR = 72 000 kT; peak date 1971
If we calculate to obtain production curves for all these scenarios and put them on the same graph with real data, we obtain:
We see that the Hubbert Linearization just before peak, with this data set, exaggerated the URR (+26%) but the peak date (1978) was not so different from the real peak date (1973). It’s the contrary for a H-L just after peak: the URR is slightly smaller (-6,5%) and the peak date is earlier (1971).
United States
The case of the United States is worth investigating since it is the "world’s leading consumer, producer, and supplier of phosphate fertilizers," according to the USGS.
Plotting phosphate production for the United States, we obtain:
Using data from 1982 to 2004, we find an URR of 2850 MT.
Calculating the production curve and plotting them with the real data gives us an estimated peak of 1988.
World production
Plotting phosphate production for the world as a whole we obtain:
Using data from 1968 to 2005 reveals an URR of 8000 MT for the world as whole.
Calculating the production curve and plotting them with the real data:
We can see from the preceding graph that we are probably on a world decline of rock phosphate production.
Population and Phosphorus
Conventional agriculture uses vast amounts of oil and gas to produce food. We have just to plot data of world population versus world oil production to see the strong correlation between them.
But oil production is not the whole story. Nutrients like nitrogen and phosphorus were also required for the “Green Revolution”.
Nitrogen is present in large quantity in the atmosphere (78% of its composition). The Haber-Bosch process for obtaining nitrogen uses one percent of all energy consumed by humans [5]. Nitrogen can also be fixed in the soil using micro-organisms such as rhizobium and azotobacters. If there is sufficient energy, nitrogen will be available.
Phosphorus may be the real bottleneck of agriculture. [6]
Population growth was only possible because we found phosphorus deposits and cheap energy to extract, transform and transport it to farms. When we plot data of world population versus world phosphate production, we find a significant correlation.
What does this correlation mean? Even if we find a real substitute for fossil fuels, it will be impossible to maintain population growth because phosphate deposits are probably in decline. It will be impossible to maintain an agriculture without recycling nutrients.
Responses to Peak Phosphorus
In some ways, the problem of peak phosphorus is more difficult than peak oil. Energy sources other than oil are available, though they all have their own shortcomings. In addition, the sun provides a steady input of energy.
Unlike fossil fuels, phosphorus can be recycled. However if we waste phosphorus, we cannot replace it by any other source. Currently we are running through the limited supplies of concentrated phosphates. Phosphate fertilizer is often applied carelessly, leading to waste and pollution. Food from agriculture goes to consumers and animals, who excrete most of the phosphorus. The phosphorus in sewage mainly goes to sea or is otherwise dispersed.
The key response to a phosphorus peak is to re-create a cycle of nutrients. F.H. King in his classic Farmers of Forty Centuries: Organic Farming in China, Korea and Japan [4] describes how returning human and animal manure to the soil enabled Asian agriculture to continue to be productive for millenia.
Sewage sludge is one method now used for returning nutrients to agriculture, although there are safety concerns about the process. Other possibilities include:
- Composting toilets and composting of waste [7, 8, 9]
- Urine diversion [10, 11]
- More efficient application of fertilizer
- Technological innovations [2].
References:
(1) United States Geological Survey (USGS). Phosphate Rock Statistics and Information. Last updated 2007. Multiple documents.
(2) Abelson, Philip H. "A Potential Phosphate Crisis." Science. 26 March 1999: Vol. 283. no. 5410, p. 2015.
(3) Pfeiffer, D.A. Eating fossil fuels, oil, food and the coming crisis in agriculture, New Society Publisher, 2006.
(4) F.H. King. Farmers of Forty Centuries: Organic Farming in China, Korea and Japan , Dover Publications, NY, 1911 (ed. 2004)
(5) Smith, Barry E. “Nitrogenase Reveals Its Inner Secrets”, Science, 6 September 2002: Vol. 297. no. 5587, pp. 1654 – 1655, www.sciencemag.org/cgi/content/full/297/5587/1654
(6) Conrad, Jim. “A bottleneck in nature”, Backyard Nature, www.backyardnature.net/phosphor.htm
(7) Jenkins, J.C. The Humanure Handbook, Jenkins Publishing, 1994
(8) Anderson, Joe. "Toilets vs. Life as We Know It." Energy Bulletin. September 2004.
(9) EcoSanRes (Stockholm Envrionment Institute). Closing the Loop on Phosphorus (PDF). April 2005.
(10) McInerney, Su. "A blooming waste," University of Technology Sydney (Marketing and Communication Unit). November/December 2006. [Short article about phosphate researcher Dana Cordell; see following entry].
(11) Cordell, Dana. Urine Diversion and Reuse in Australia: A homeless paradigm or sustainable solution for the future? (Master's Thesis). Department of Water & Environmental Studies, Linköping University. (PDF version.) February 2006.
Déry, Patrick, « Pérenniser l’agriculture » Mémoire pour la Commission sur l’avenir de l’agriculture du Québec, avril 2007, www.caaaq.gouv.qc.ca/userfiles/File/MEMOIRE(1)/02-07-Saguenay-Dery,Patrick.pdf (in french only)
Brown, A. Duncan. Feed or Feedback: Agriculture, Population Dynamics and the State of the Planet, International Books, 2003.
Gunther, Folke. Vulnerability in Agriculture: Energy Use, Structure and Energy Futures, presented at the INES conference, THK, Stockholm, 2000.
B.Gumbo, H.H.G. Savenije and P.Kelderman. 2002. Ecologising Societal Metabolism: the Case of Phosphorus. In: Proc 3rd Int Conf Environmental Management. 27-30 August 2002.
Steen, P. 1998, Phosphorus Availability in the 21st Century: Management of a Non Renewable Resource. Phosphorus and Potassium.
~~~~~~~~~~~~~~~ Editorial Notes ~~~~~~~~~~~~~~~~~~~
Patrick Déry is a "physicist, energy, agriculture and environment analyst and consultant in Quebec, Canada."
Bart Anderson is a former reporter, teacher and technical writer. He currently is co-editor of Energy Bulletin.
Patrick sent the original article to Energy Bulletin in April. I had never seen anyone apply the concepts of peak and Hubbert Linearization to phosphorus. Even though I had known intellectually that phosphorus supplies were limited, it wasn't until I read Patrick's paper that I realized how urgent the situation is.
To make Patrick's ideas more widely accessible, I added background information and did some wordsmithing, but all the original ideas are his.
For more background, see Peak phosphorus: readings (Energy Bulletin).
-BA
“Men argue; nature acts.”
—Voltaire
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I guess I am uneasy with this analysis - unless you can show that mankind has searched most of the planet for more phosphorous and come up empty, then it seems entirely possible that current reserves are only limited because nobody has bothered to go out and look for more.
The curves show a plateau in total production, but is that because it gets harder and harder to find more phosphorous, or is it because improved agricultural techniques to minimize topsoil losses and to reduce nutrient runoff have reduced the demand for more phosphorous?
I share the same concerns. Do we have discovery data for phosphorous deposits? I was wondering if a discovery peak exists. The use of phosphorus has also been limited in certain country (ex: France) because of problems of eutrophication of water.
It seems intuitive that the phosphorus deposits have to be very easy to access for it to be profitable. Phosphate rock goes for around $30 per ton, while a barrel of oil is about $70 for 0.136 tons (or $500/ton). That must have some impact on how far and deep we will go to recover it ... at the present time.
I think you can rule that out, because the phosphorous is used by the plants to build themselves. It's a cycling element, not a catalyst, so it needs to be renewed after every harvest. A typical ecology keeps it local via dropping leaves, faeces and animal corpses. However, if you harvest and export it, it is necessary to supply new P from either a finite source (mineral deposits or the soil), or import it from elsewhere, preferably from those that consumed it in the first place, to close the cycle.
The very fact that runoff and rivers have problems with eutrophication suggests that excess phosphorous has been over-applied, and is washing into various waterways. As humans become smarter about preventing this, then demand for phosphorous would go down.
Eventually you would reach a theoretical point where the only phosphorous that is applied is used by the plants that are shipped out, but even then some of it is recoverable from sewage.
I think you are correct that farmers are becoming better at managing fertilizer application. Have world sales of phosphate decreased because of greater use efficiency, or are sales still rising with previously mined phosphates stores being depleted to compensate for lower extraction rates?
Another reason for run off problems, in addition to over application, could be the type of phosphate applied. I believe those superphosphate products have been manipulated to increase solubility and rapid availability to plants, but since the soils are mostly dead and organic matter levels are so low, any excess phosphate runs off fast.
Organic farmers use products that are less immediately available, have slow release properties, and therefore don't have these run off problems.
In areas with low soil PH, runoff is more unlikely. In soil conditions with a PH of say... under 5.3, P tends to bond with soil particles, more so in fine/clay soils which have more surface area per gram.
Liquid calcium or Lime will raise the PH and make the "P" water soluble again.
N,P, K & Fe are not water soluble at low PH. So the mechanism of runoff should be of low concern in soils with PH below 5.3 or so.
See: cation exchange capacity
Conveniently, Fertilizers lower the pH. If the pH goes below 4.5, then the plants suck up potential heavy metals (and I don't mean Black Sabbath). Below 3.5 pH, Aluminum becomes soluble and everything dies.
Expanding further, the fungus and bacteria association with the plant diminishes with these fertilizers (and much soil life is killed). The plants become bloated with water, which the herbivore insects take note and feast. Then the insecticides kill these "pests", but also the insect life in the soil. Without the insects to burrow into the soil, bringing down fungi, bacteria, and protozoa to the roots, the soil goes anaerobic.
Anaerobic soil means low pH, so even applications of Lime or whatnot don't work for long, as the nutrient plugs are already gone, the bacteria fight to keep a low pH, and nutrients wash out. Even worst are the blights that can now infiltrate an unprotected ecosystem (note fungi above).
http://soils.tfrec.wsu.edu/mg/chemical.htm
Aluminum starts becoming water soluble at 6.0 and lower.
PH of 4.5 is a bit too late, the nitrogen ammonia cycle is basically stopped at 4.5. At a PH of 5.6 nitrogen fixation by plants starts to be problematic.
Water logged soil is anaerobic, re: lack of oxygen.
Off topic but still an energy post. Both heavy duty and alkaline batteries use carbon and zinc electrodes but heavy duty batteries use an acid electrolyte and alkaline batteries use (you guessed it) potassium hydroxide. Alkaline batteries are mucho superior in every respect except initial cost and I never knew why until I saw your post. You do NOT want your electrode, in this case zinc, dissolving in your electrolyte.
Nickel Iron batteries, touted by one of us, last essentially forever because the electrodes are essentially insoluble in potassium hydroxide. They have other issues, but they last forever.
I shoulda known quoting from my Permaculture class. However, the pH and Aluminum problem is still around 3.5 pH when no plant can survive. The issue relates to the interaction between Phosphorus and Aluminum across a spectrum of pH.
http://www.plantphysiol.org/cgi/reprint/18/4/708.pdf
I'm sure there are other references out there.
Yes, water logged soil is indeed anaerobic. I'm trying not to write a book inside a comment, so have compressed the whole process of tilling, fertilizing, biocides, etc that comprise our conception of food "production" as fundamentally flawed and always ends in depleted soil and desertification.
PH of 4.5 is a bit too late
Let's not split hairs to fill in the 0.5 pH to go. It's out there, if you want to find a plant that "survives" it. However, below 3.5 is certainly a dead zone.
Stream of consciousness. Nobody thinks without phospourus. Aluminum causes phospourus to precipitate. Aluminum is implicated in Alzheimers.
Blood is a mild base. Unless you suffer from acidosis. CO2 makes carbonic acid. Therefore exercise is bad for you. Couch potatoes have the best brains on the planet.
Okay this all makes perfect sense, but then again I keep hearing about the enormous swine manure problem and how it poses such an extreme biohazard.
Is this due to a lack of proper resource management on the part of the pig farmers? Is swine manure a good source of phosphates?
There's a lot of phosphorous in pig manure. It limits the amount of manure you can apply to an acre which means you may not be able to apply enough to meet nitrogen requirements.
You can either top off the nitrogen with Haber-Bosch fertilizer or you can go to old-fashioned crop rotation using legumes like soybeans, clover or alfalfa.
I just wonder where all the sediment and animal wastes are disposed of ultimately. Certainly we're not supposed to dump them into lakes and rivers. How much phosphorus is in landfills of any type? Anyone know?
Manure is a good source of methane if digested anaerobically, and there has been noise about growing algae on sewage effluents for tertiary treatment (which includes phosphorus removal). Then you've got the people touting biofuel production from the algae. This looks like the better part of a cycle.
I'd like to know if the ash from gasified algae cake contains enough phosphorus and the like to be worth shipping. Does anyone have a chemical analysis of dried algae?
Actually shortages of key resources may crop up in unexpected places. One that I track informally is Tantalum. This is a rare-earth metal that is used in many electronic devices.
It's properties are what allows the high degree of miniaturization in items like cell phones. There are substitutes, but they all have drawbacks.
The supply of Tantalum is limited to begin with and their are continuing battles in the areas in Africa where it is mined over control of the resources. It is impractical to recycle it since the amount in each cell phone is insignificant, but the total over the billions of phones made and discarded adds up.
Personally I think the first choke point will be fresh water and arable land. To produce fresh water from non-potable sources (such as the sea) is very energy intensive and that gets us right back to the same place: energy use vs climate change vs "peak".
The whole idea of growth and unlimited consumption needs to be addressed, present trends are unsustainable.
The whole idea of growth and unlimited consumption needs to be addressed, present trends are unsustainable.
Potable water, Fossil Fuels, and Phosphorus are leading my list on 'society limiters' that there are no simple 'technoswaps' for. With the economic effects of the end of under priced energy being the 1st hit of many.
But hey, we've got plenty of hope, right you technofixers?
(listens to the sounds of crickets here on the high ground)
It is impractical to recycle it since the amount in each cell phone is insignificant, but the total over the billions of phones made and discarded adds up.
All depends on the price. Eventually you'd have people scrapping the capacitors off the boards for the Tantalum.
Tantalum capacitors have drawbacks too. In addition to being a blood metal. Large ceramic caps have superior electronic properties but will make your cellphone slightly bigger.
Actually minaturisation isnt all its cracked up to be. It's basically a marketing tool - except for missiles and satellites. If we didnt have small cell phones how bad would that be? [Hint: you wont catch me with one any size..]
People who HAVE to communicate could carry a backpack or whatever.
We can live without tantalum capacitors and resistors. Ceramics can be even smaller.
tantalum capacitors and resistors
Sure enough - tantalum is now to be found in (some) resistors.
I used to work for an air force contractor and I designed in big f--king ceramic capacitors everywhere because of reliability issues with tantalum. It might weigh an extra microgram but that's someone else's problem. When your cellphone goes dead, you just buy a new one. And you'll probably buy a new cellphone in three years even if you already own a perfectly good one.
Tantalums are polar which means off the bat the guys who took a three week course to be certified as the only people on base qualified to pick up a soldering iron will install it backwards. In a best case scenerio, I still have to spend a day writing a test plan explaining how some airforce schmuck can demonstrate that it is installed correctly. The testplan has to be approved by four levels of management, the QA manager, the air force, the safety committee, and the trilateral commission, save my immediate supervisor none of whom know which end of a diode is up. It then gets an official document number record from the person who does nothing but keep track of paperwork so that all the other documents can cross reference it by number. Tantalums will easily cost the air force an extra ten grand. And that's before someone figures out it is a strategic metal that only comes from Congo and asteroids.
Bart, Patrick, PG,
Thanks for an interesting post. Are reserve figures available? How do they compare with the Hubbert linearization?
So, all that phosphorous that goes into the seas stay on the water or go to the botton?
How easy would it be to recover it on any of those cases?
That is what really worries me. Any P that sinks into the deep sea is gone for an eternity. I hope the amount we dug up makes up for the amount we have been letting, and will be letting, to wash away.
Phosphorus in the ocean is available to sea life.
This is one reason why fish like salmon are so necessary. They go to the ocean as fry and return as adults, with a large body mass of phosphorus (and potash and calcium and nitrogen). Animals like bears take the nutrients out of the streams and return most of them to the land; if we tried, we could improve that process. We couldn't engineer a better aid to nutrient replenishment.
As long as it stays on the continental shelf, that's as good as on land. But the deep sea trenches are virtually bottomless, and much more prone to tectonic recycling, which puts it out of reach. Also, the amount of nutrients that run off are too much for ecosystems to absorb, except for a few short-lived algal blooms.
conncentrated phosphorus in the water run-offs ia also terrible for the ecosystem. The "dead zone' at the mouths of our major agricultural river systems is caused not only by nitrogen causing the algal blooms but by phosphorus. If you all will recall, thats why they took the phosphates out of detergent about 25 or 30 tears ago, and its also credited with changing the vegetation in the everglades downstream of the American Sugar fields.
There are some less concentrated forms of ruck phosphate though, and I'm thinking about green sand, which is called glauconite?(some real geologist, help!) and that's fairly common, but the phosphorus is much lower than phosphate rock.
The real problem is population overshoot. When I was born in 1951 the world had less than 1/3rd of its current population, about 2 billion people. If the populaion had stabalised at that level we would not have a detectable global warming problem yet, a peak in energy production yet, or farming practices killing the oceans and rivers.
Get a vasectomy or tubes tied after one child everybody. Bob Ebersole
This reminds me of a study done to determine how the northern plains rejuvenated after the ice age. It was assumed that buffalo poop was the main 'culprit' but it turns out that 85% of the poop on a given area comes from birds, those last of the 'extict' dinosaurs rather than land mammals. Bird poop and seed transport are all that is needed to restore or move a boundary on a rapid basis. I betcha ther's lots of phosphorus in birdshit. And if we stopped crapping in the rivers and ate local... maybe WE are at Hubbert's peak?
Salmon returning to rivers to spawn have grown in the ocean.
This returns nutrients to the land as the salmon die and are carried away from river banks by scavengers.
Migratory river eels in Europe do the same I suspect.
Some local officials around here are open to composting toilets, but laws haven't changed yet. Working on it.
I think it was Frederick Soddy who said "No phosphorus no thought."
Quote: Ohne Phosphor, Kein Gedanke
Without phosphorus, there would be no thoughts.
Originator: Attributed to Ludwig Buchner (1824-1899)
"The real problem is population overshoot. When I was born in 1951 the world had less than 1/3rd of its current population, about 2 billion people. If the populaion had stabalised at that level...."
So Oilmanbob, did you procreate more than the authorize 2.1 times? I did. Unfortunately, our natural compulsions drive us inexorably toward overshoot.
A seductive explanation, but not necissarily true; While the earth clearly can't support population explosion forever, its not obvious that 2 billion is supportable forever and seven billion is far to much.
if you are so inclined....
http://science.reddit.com/info/2g3n7/comments
http://slashdot.org/firehose
This is an incredibly interesting article not for its analyses of phosphorous but more for its analysis of Hubbert Linearization.
Dr. Déry did H-L on Phosphorous from a number of angles on the island of Nauru. The question that arises is whether the results tend to be similar with H-L analysis of various resources. Specifically, is it always true that an H-L analysis using data from before peak yields a higher URR and a later peak date.
I doubt that this is the true but if it was, it would certainly be relevant to our current H-L analysis of World Oil Production since we are very near the peak.
I would love to hear opinions from some of the contributors who are more familiar with the Hubbert Linearization methods.
Rick
My Favorite Google Reader Stories:
http://www.google.com/reader/shared/01423328269523419567
As noted in the above link, "In Defense of the Hubbert Linearizaton Method," the post-1970 and post-1984 cumulative Lower 48 and Russian oil production has been very close to what the HL models predicted, using only production data through 1970 and 1984 respectively.
I think that the HL method works for so many different natural resources for a very simple reason--we tend to find the biggest, and cheapest to exploit, reserves first. We then focuse on smaller, and more expensive, reserves.
In regard to oil specifically, peak oil production is primarily a function of the rise and fall of the giant oil fields. Empirically, the function of oil companies in post-peak regions like the Lower 48 and North Sea is to slow the rate of decline in conventional oil production.
You're sure right about the giant oil fields. The peak year for discovery of oil in Texas was 1930, when the East Texas field was discovered. The peak of Texas production was 1950, when East Texas came off its plateau, and also when the US as a whole became a net energy importer.
I'm sure its all coincidence. (sarcanol alert)
Bob Ebersole
Note that the final Texas peak was 1972.
This suggests it would fail for substances whose more expensive reserves are much larger. Has it been applied to gold?
--- G. R. L. Cowan, former hydrogen-energy fan
http://www.eagle.ca/~gcowan/Paper_for_11th_CHC.html :
oxygen expands around boron fire, car goes
In regard to conventional oil exploration, it is a simple matter of probability. The bigger the field, the more likely it is that we will find it. Large conventional oil fields result in the most bang for the buck, where we tend to see a combination of both high quality reservoirs and large volumes of oil, e.g., the north end of the Ghawar Field.
It's a simplification, but basically oil companies are now looking for smaller fields, with good reservoirs, and/or for resource plays like the tar sands--large, but with various problems, starting with a virtual inability for the bitumen to move to the wellbore, without some kind of energy input.
In any case, IMO what drives the Hubbert Curve is the rise and fall of the giant oil fields that tend to have both high quality reservoirs and large volumes of oil.
http://www.epa.gov/radiation/neshaps/subpartr/more.htm
http://www.ecan.govt.nz/NR/rdonlyres/DF4F15C7-2368-4210-9E4A-B72BD911277...
http://www.fertiliser-society.org/Proceedings/UK/Prc400.HTM
http://jnuenvis.nic.in/subject/arsenic/poisoning.htm
It's hard to make a comment about something that should never of been used in the first place, yet has boosted our population regardless of the health hazards. By not using it, starting now, we endanger billions of lives. Yet continuing to use it leaves us with mounting medical concerns.
I couldn't find the article about random tests of fertilizer sold at the store, but the heavy metal contamination is stunning. It makes me suspicious of anyone offering food from their garden. I'd love to see a study done to see what contamination exists at the grocery stores and how much it takes for us to bioaccumulate these toxins. You'd think it was in the health insurance industry's interest to find out.
semaley
Thank you for those links, I'm going to bookmark them. Everbody, take a look at them. The tell what kind of rocks, the processes needed to make rock phosphate water soluble,, the residual heavy metals of concern (arsenic, cadnium, lead). This is what we all need to read to discuss the problem intelligently. Bob Ebersole
Ummm...my understanding of the healthcare industry's "interest" is chiefly to deny services to those who request them, i.e., to turn a profit. Of course, this applies only to the US...
This is part of the total set of oncoming crises facing homo sapiens today. It's not just peak oil but resource depletion across the board - energy sources, various critical minerals, arable land, fresh water, destruction of biological habitat, loss of ecological diversity, climate change, and always always always the 800 pound pink elephant in the room - overpopulation.
We cannot attack these problems in isolation. They must be attacked all together at once with solutions considering all of the other factors. Failure to do this will result in solutions to one problem that worsen other problems.
Sleep well tonight, people. Just ignore the fact that you are passing a poisoned, dying, depleted world to your children and grandchildren. After all, it's their problem and not yours, right?
"The greatest shortcoming of the human race is our inability to understand the exponential function." -- Dr. Albert Bartlett
Into the Grey Zone
You forgot to mention the corporatocracy that will fight tooth and nail to keep us on the same path...
"You can never solve a problem on the level on which it was created."
Albert Einstein
"...and always always always the 800 pound pink elephant in the room - overpopulation."
That is too true. I have had no bad experience rolling out PO to friends and colleagues; they listen politely, and sometimes discuss/ask questions (they seem interested in the Cantarell saga in particular). But a sure-fire way to kill the conversation dead is bring up population. I'm pretty sure dieoff is the only way the population is going to come down.
PLAN, PLANt, PLANet
Errol in Miami
I'm pretty sure the only time the population is reduced by one is when somebody dies as well.
"This is part of the total set of oncoming crises facing homo sapiens today. It's not just peak oil but resource depletion across the board - energy sources, various critical minerals, arable land, fresh water, destruction of biological habitat, loss of ecological diversity, climate change, and always always always the 800 pound pink elephant in the room - overpopulation."
This is a great point. Especially in the last hundred odd years people tend to extract resources rather than recycle resources. This is mostly because now we have the ability to do so. Where people did recycle it was because they had to.
In the third world much agriculture is slash and burn. This is a way of mining fertilizer. Over long periods of time plants and worms have managed to extract sufficient minerals from the ground to build up a forest. Farmers burn the forest releasing the minerals then grow crops for a few years till the minerals have been depleted then they move on.
It doesn't have to be this way. We now have enough knowledge of chemistry and physics and biology to devise systems that will let us extract food without depleting the land and without requiring the addition of large amounts of inorganic fertilizers. As usual, this requires large changes in our organization with different winners and losers and the current winners won't easily let go of their positions.
My favorite phosphorous story is that it is ice ages that fertilize boreal forests and they decline before the next glaciation owing to lack of phosphorous. The grasslands of the Steppes and planes are perhaps signs of lost forests.
Chris
ice ages that fertilize
http://www.remineralize.org/
Their position is you grind up rock and the ground rock makes the land fertile.
They leave out another very important ingredient: worms (and their associated micro-organisms).
Worms require ground-up rock (abundant in regions where ice from glacial periods has ground up surface stones) to process food in their gizzards. Some people have suggested that is is one of the reasons for such poor soil in places like Australia - it missed out on being "iced" during the last glacial period, and has not supported a decent worm population.
In places in the northern hemisphere such as England, worms process around 10,000kg of dry soil per acre per year. They, and their co-organisms are what keep the soil healthy for the most part.
"You can never solve a problem on the level on which it was created."
Albert Einstein
They leave out another very important ingredient: worms
Remember tho - most of the worms now seen in the US of A are imports. The native green tinted ones are 'lazy' VS what came over from Europe.
My memory says fossil record shows many 'european imports' having existed in North America before one of the big ice ages, then not after.
Remineralized my yard & garden - check
Composts own humanure & adds to garden - check
Worms in my yard & garden - check
Resident Toad in garden - check
Lots of beneficial insects (minus formerly seen honey bees) - check
Hummingbirds (and many other birds, minus formerly heard Whippoorwills & Bob Whites) - check
Windmill in my backyard - check
PV arrays - check
Solar hot water roof panels - check
Fertile homestead & garden - I'm trying my best to make it so
Interesting nature discovery today: Found an Intermediate sphinx moth in my greenhouse (must of flown in open door); very lovely creature but apparently unknown before in this area.
Who here watched the Perseids last weekend?
check :-)
I watched but only saw a few. How may deer to you get in you garden?
Generally, forest gives way to grassland as rainfall decreases.
Will everyone please note, there are only two 'o's in phosphorus. Save your fingers and look smart.
At the USGS Mineral Commodity page for phosphates, there are PDF files that note that
and reveal that in 1995, phosphate rock production was 0.137 billion tonnes, leaving reserves of 11 gigatonnes, and in 2006, production 0.145 gigatonnes, reserves 18 Gt.
There's only so much one can eat, so I would expect extraction rates to increase only in pace with population.
How much dissolved P is there in the sea?
--- G. R. L. Cowan, former hydrogen-energy fan
http://www.eagle.ca/~gcowan/Paper_for_11th_CHC.html :
oxygen expands around boron fire, car goes
Virtually none. It must fall to the bottom, as marcosdumay and slx suggest.
--- G. R. L. Cowan, former hydrogen-energy fan
http://www.eagle.ca/~gcowan/Paper_for_11th_CHC.html :
oxygen expands around boron fire, car goes
This is certainly a very thought provoking piece, but I think it's a little dangerous to draw strong conclusions from Hubbert linearization alone since it is such a rough model - I much prefer to have multiple lines of evidence supporting a conclusion.
The most salient thing I'd like to see here is the price graph over time. If we have had a period of higher prices with no supply response, that would tend to strengthen the case that this is really a resource limitation, as opposed to some transient or demand-side issue. I cannot quickly find price data on the net - has anyone found it?
I agree and don't forget discovery curves.
You need all three pieces of information.
And finally you need to know if their is a political cartel in action or war etc. Remember silver. So you have to include major above ground events. But I think discovery is the most critical factor. HL follows discovery it to normalize the exploitation phase post discovery.
It was very interesting to see HL applied to the coal fields. As Dave R. pointed out, the location of the coal was well known far before it was mined. At yet coal production followed a bell curve.
After seeing Nate's graph of EROI has a bell shape, I wondered if the Hubbert curve is caused by changing EROI. The slow start ramp is because it takes a lot of investment to bring any production on line. Profit volume is small so self capitalization is small. As investment is paid off EROI increases (you get lots of resource through paid off wells and pipes) and then the main fields deplete and reinvestment is lowered by falling EROI, depletion gets ahead and the curve turns down.
Jon Freise
Analyze Not Fantasize -D. Meadows
I'm glad to see that Patrick and Bart referenced The Humanure Handbook, which describes one very simple and effective approach to recycling, among other things, phosphorus. Note that the text of the book is also available online.
Diesel, natural gas, and electricty may play a part in peak phosphorus.
We are looking at interesting problems.
http://www.prosefights.org/pnmgas/pnmgas.htm
http://www.prosefights.org/pnmelectric/pnmelectric.htm
slowly and carefully, we hope.
Is infinite growth possible on a finite planet?
Infinite growth in what? "Material and energy flows"? Clearly not. "Perceived value by humans of the final form of the finite material and energy flows"? Perhaps...
I suspect a lot people who repeat the "can't have infinite growth on a finite planet" line haven't really thought much about what "infinite growth" means. Especially in the context of a declining or at least stable human population. It could well be thousands of years before we run into any significant limits on the amount of energy that we could bring under our control. But it has to be said that the risk of our technology escaping our control becomes ever greater, and there may be little realistic chance of humanity as we know it now surviving that long. I like the idea of us settling various planets and moons whereby some settlements have a deliberate policy of limited technological development (a common theme of some sci-fi writers, interestingly enough). That way if one planet's worth of humanity gets subsumed by nano-goo or a bio-engineered disease or nuclear holocaust, it wouldn't be the complete end of us. It would be disappointing if it had to be Earth that suffered such a fate though.
I hang out a bit in the fountain pen collecting world. An Giant Red Parker from around 1920 just sold on ebay for a little over $5000.
I love the Japanese aesthetic - they had limited resources and made the most of them. There is a whole cult of teacups. Some very simple rustic teacups are just so precious, they are priceless.
Many times and places through the human past, with very limited material resources, people have soared to sublime levels of truth, beauty, and goodness, that modern materialism has no ability to appreciate or hardly to perceive.
Of course the population will come down. 6 billion is not sustainable. Resource consumption will decline, even per capita.
But maybe somebody will figure out how to prove Goldbach's conjecture - why cannot mathematics continue to blossom on a very low budget? Fewer distractions! Even the ancients managed to accomplish great marvels with their limited resources.
Very interesting post, but the "World Rock Phosphate Production" red curve you fit to is significantly asymmetric about the peak, particularly in the tails. Is this a fit to the sigmoid function in the logistic derivation? If it is, the curve should be perfectly symmetric about the peak. (Eyeballing, it might actually improve your fit if you redo it, albeit the HL chart is alright as is).
What I point out may be a nit but as you may well be aware, global warming climate scientists are being raked over the coals by Freepers for an error correction that you can barely even detect in the graphs:
http://www.washingtonmonthly.com/archives/individual/2007_08/011889.php
http://scienceblogs.com/deltoid/2007/08/_if_i_summarized_glenn.php
Slightly off the thread, but I have to comment on the perceived shortages of strategic minerals ie, copper, tungsten, tantalum, et cetera that have been floating around-- this thesis applies to phosphorous, too, but it's probably best just to recycle that from animal/human manure (much more appetizing and acceptable if the manure goes through a digester, yielding tasty methane for power)
-- we're running out of nothing. Where were you in 1969? What do you think the copper reserves of the moon are? Or better yet, the Apollo asteroids? Grab an m-type (metallic) asteroid, and a big mirror; a small asteroid could provide all human demands (at current levels) for several years. Mining it in Space means no pollution, and no power is taken up since it's all solar. (solar power, in space? Well, it's where they keep the sun...)
Drop raw or processed materials into the Gobi/Sahara/Mojave desert, and enjoy.
No current need for phosphorous, but since mining phosphorous isn't exactly environmentally friendly, high eco-taxes could make asteroid mining cost-competitive with that as well, depending on to-orbit launch costs for your mining equipment.
Also, most of the readings seem to ignore arctic phosphorus resources, in the Siberian and Canadian tundra. I hear there's some, and Global Warming will make all of that all the easier to access.
Dude. How much energy do you think we'd need to "grab an asteroid?" Plus, dropping a football-field size asteroid on Earth results in destruction greater than a nuclear weapon, and vaporizes the asteroid anyway.
Space travel fuels have never been mined, refined and produced, except with fossil fuel, and machinery which itself was made with fossil fuel. By definition, the amount of energy in the fuel was less than the energy in the fossil fuel so consumed.
Space travel is made of fossil fuel!
Getting to a near-earth asteroid from LEO takes about 5.5 km/sec of delta-V. Getting material back requires only enough push to get onto an earthbound trajectory; aerobraking takes care of the rest.
... is a foolish thing to propose, when the optimal size is probably between a kitchen table and a car. Form it into shallow cones (draggy but stable at hypersonic speeds) and add a layer of slag as an ablative heat shield.
Space travel has been powered by the Sun. Fuel is actually one of the cheapest elements of space launches. If you required solar electricity to produce liquid hydrogen to put a mission up, it wouldn't increase the cost very much. Once you're away from the draggy environment of LEO, cargo can travel the inner solar system using light sails.
Check the fine print. 5.5km/s is for a typical asteroid. We can go from LEO to Mars or Venus for 3.5km/s. The SURFACE of the moon is a bitch because you can't aerobrake on the moon.
Check the delta vee for an earth trojan asteroid. We only need ONE asteroid, not the entire asteroid belt. That's like saying typical earth rock contains .000001% gold. Nobody mines random rock for gold.
Okay, I was sloppy and pessimistic. It's even better than that (you need about 3 km/sec to go from LEO to escape).
Escape velocity is 11.2km/s. Orbital velocity is 8km/s. It takes more energy to go to orbit Mars than escape because you have to do an orbital insertion burn when you get there. Or aerobrake.
Anyways, we don't care what the delta V to land our space craft on an Earth trojan asteroid is. We want to know what the delta V is to move a billion ton asteroid into earth's orbit. I wonder what greenpeace will say when you tell them we are going to aerobrake the asteroid when it gets to Earth? Nothing can go wrong, trust us. We got a bridge in Minnesota to sell you.
Why would you want to move the whole asteroid? Do your beneficiation on the asteroid and just move the product.
When you tell the public (not the NOPEs) you tell them that the ablated slag from the heat shields will give them some relief from the global warming and really beautiful sunsets.
Why are they giving data for the MOONS of Mars? That means you have to STOP with no aerobraking. Who wants to go to Phobos anyways? Stopping more or less doubles your fuel consumption. The moons of Mars are captured carboneaceous chondrites. Valuable as that organic material will be to Martian settlers eventually, we want to bring metals to earth.
I have a lot of respect for Wiki, but that is not a neutral article. Everything they say is true and none of it is relevant to the problem at hand.
The energy cost of space travel is absolutely dominated by the fuels required to escape gravity. Those fuels are ridiculously expensive to produce and store at near-absolute-zero temperatures, even with cheap oil.
Once you're in space, of course nobody uses fossil fuel! Fossil fuel assumes free oxygen, none of that in space.
Space vehicles use rocket propulsion, photovoltaics, or nuclear reactors, mostly.
But when we start talking about space vehicles that can catch a mineral-rich asteroid, and then break it up into cone-shaped car-sized chunks, and send each chunk down to earth, accurately enough to hit a specific desert - that's going to require a lot more energy than you can get from a space vehicle's reactor. Or an incredibly long time.
If you consider how much fossil fuel it takes to produce liftoff fuels, how could asteroid mining ever compete with conventional mining? I guess you're assuming that we'll lift up a fleet of mining ships, and then keep them up there? Refueled by the occasional fuel ship?
Sounds like an unlikely project for once fossil fuels become permanently super expensive...
Dimethyl hydrazine is a very common fuel used in space, derived from fossil fuel (it's hypergolic with nitrogen tetroxide).
On the local advantages, which include continuous solar energy (effectively unlimited free process heat) and ease of moving large masses. There are also no environmental or other restrictions.
You're right. That's why nobody's proposed doing it that way. On the other hand, if I've got heaps of process heat to separate raw asteroid into metal and slag but only a little electric power, it only takes 500 watts to launch a metric ton per second off an asteroid with a 1 m/sec escape velocity. Once away from the parent body the rest can be done with light sails. They may be slow, but if you can make metal foil you can crank them out by the acre.
I just don't see this stuff getting off the ground fast enough. As petroleum dwindles, everything that depends on it will compete for the dwindling resource. New ideas with high risk will be avoided, in favor of old ideas with low risk.
The only interplanetary starships ever made, even during the peak of oil discovery (1960s), when optimism was highest, all they've ever done is take pictures.
When there is less petroleum every year for everything, who will be denied first? The military? supermarket deliveries? suburban commutes? Or unprecedentedly risky interplanetary space missions, of a kind we've never even tried before?
When there is less petroleum every year for everything, who will be denied first? The military? supermarket deliveries? suburban commutes? Or unprecedentedly risky interplanetary space missions, of a kind we've never even tried before?
Look at the present economic/political system. Where the group who writes the rules get to select who benefits and who is punished. And how it is enforced.
Whatever allows 'the leadership class' to take part of the skim from the process proposed, is what will happen.
And I see satellites for weather/communications being put up before 'harvesting metals from space to drop back to earth' gets done.
The 'lets to space and go get stuff' (or worry about the lack of P for crops) seems to also be dependent on needing the 'stuff' for a large population. Why worry about space mining if the population situation is going to change in a lower direction?
I used to not work for the MI company that f--ked up what is suppose to be the current generation of weather satelites. The birds that are up there are old and falling out of the sky and it is anybody's guess when the gubberment is going to come up with the dollars and the competence to replace them.
Communications satellites have been done. Anybody's guess whether fiber optics has become cheaper. The third of a second delay to geosync orbit and back is a major pita.
We'll harvest a 100,000 year supply of ALL the platinum and nickel group metals as soon as a hedge fund scraps together a hundred billion dollars. I figure work will start in 2009.
The birds that are up there are old and falling out of the sky and it is anybody's guess when the gubberment is going to come up with the dollars and the competence to replace them.
Once the 'benefit' is 'quantified' - it'll get done. The lives that notification of hazardous weather is a simple one, so could crop damage/plating info. Far more quantifiable than many other spending priorities.
If the 'leading interest' in local TV news is 'the weather' - I can't imagine how hard it would be to sell the public on weather birds.
Communications satellites have been done. Anybody's guess whether fiber optics has become cheaper. The third of a second delay to geosync orbit and back is a major pita.
But there are places with no other option - so 1/3 of a sec looks damn good. Hence my thought - communication and weather birds will still go up. So will spy birds.
We'll harvest a 100,000 year supply of ALL the platinum and nickel group metals as soon as a hedge fund scraps together a hundred billion dollars. I figure work will start in 2009.
Now there is an argument about 'fiat money' VS 'commodity backed money'. If money was backed by metals, would a nation go into space to get metals to debase the completion or expand their money base? Now imagine the protests....'you can't do this, it would bring on inflation and effect the earths orbit!' Hehehehehehehe.
A nation might not but if it was clear there is a very large return on investment, a hedge fund would. A hedge fund is only interested in Federal Reserve policy when it affects how they can make some money. Inflation is someone else's problem. Do you think the conquistadors cared that the inflation from all that gold they brought back to Spain ruined their nation as a Great Power?
It will be very sad if we have the ability to continue to explore our universe and gives it up for a smaller decrease in consumption. Gathering knowledge is something that makes life worth living and a culture worth having. (But we better do it in efficient ways, feelings such as mine can be misused to avoid chage within inefficient organizations. )
When there is less petroleum, the poor will be denied first. The price goes up and whoever can't pay gets voted off island earth.
I figure the government is going to piss away our money anyways, we might as well piss 0.7% of it on NASA. Sort of like making biodiesel because we are going to supersize our fries anyways.
Liquid oxygen is made by distilling air. In any quantity, it is cheaper to build a still on site then to truck in large quantities of LOX. The distilleries are custom built. I was trying to get a number for the energy it takes to distill air but failed. I can calculate the energy required from thermodynamics, but I don't know how efficient real world stills are. Unless I waste the time of someone in the business by sending him an email, I'm not sure how to get real world data.
The Saturn V burned kerosene and LOX and the third stage of the apollo moon rockets were LH2-LOX. IMHO apollo did it right. For going just to earth orbit, hydrocarbon fuels are good enough and the complexity of LH2 outweighs the benefits. If you have the ambition to go further, it should be with LH2 if it is with chemical energy, because you have to burn a lot of kerosene to get that weight into orbit. These days we have ion engines and other stuff with high Isp but low total thrust, and there are some more parameters to consider.
For back of the envelop calculation, assume the first stage is a Saturn V with 6 million tons of kerosene whatever it holds, and the LEO to earth trojan asteroid engine is solar-electric ion propulsion.
Now we have to figure out if we are benefacting the ore onsite or shipping the whole darn asteroid to earth's orbit. Either way, we would use a solar powered flywheel powered massdriver to throw chunks of asteroid in the opposite direction. I haven't done the calculation as to whether we are better off bring high explosives with us from earth and powering the mass driver with that.
This entire exercise assumes the powers that be won't let you use nuclear powered anything anywhere. Just take it as a nonnegotiable ground rule for the exercise.
There's enough math here for an entire article if anyone wants to do the math. Maybe someday I'll post my numbers in my blog but I won't have the time anytime soon.
http://www.astronautix.com/engines/f1.htm
Assume your main rocket engine is this one developed in 1959. There were five of these on a Saturn V, but we can use as many as we need. The rest of the mission is solar powered. So now it is just a matter of guestimating the payload mass necessary.
Google (asu "kWh/kg O2")
Medical devices and some medium-scale things remove the nitrogen by adsorption on zeolite. This takes about three times more kWh/kg O2 than distillation.
--- G. R. L. Cowan, former hydrogen-energy fan
http://www.eagle.ca/~gcowan/Paper_for_11th_CHC.html :
oxygen expands around boron fire, car goes
we're running out of nothing.
True, so long as you are not constrained by energy to re-separate the material (reverse entropy).
Or constrained by economic models that are dependent on low cost inputs to continue to function.
Can someone actually explain why phosphorous is non-renewable? That is, where is it all going that we can't recycle it?
At one level nothing is renewable. Despite our best efforts nothing is 100% renewable. On a more practical level, P is largely renewable in some ecosystems. For example, in tropical rain forests the leaves and branches fall to the forest floor where they decay releasing their mineral content for uptake by the roots of the trees. Some P probably washes away with rainwater while some P is released from the soil by the action of worms.
In our style agriculture we apply fertilizer to the soil to raise the soluble P to a useful level. Much of this washes away with rainwater so it needs to be replenished yearly. Most of the rainwater drains away to the ocean carrying the P with it. We also remove the agricultural products from the land rather than composting it so little P is returned to the land.
"At one level nothing is renewable."
And at another level, everything is.
Unless your argument is that the Earth is getting lighter and lighter and lighter, until one day, it's weight is down to zero and it just shrinks away! :-)
RC
Remember we are only one cubic mile from freedom
The non-renewability has a lot to do with entropy. As Phosphorus continues to disperse through use, it becomes harder and harder to extract. Only applying more energy will enable us to concentrate it, thus overcoming entropy.
Helium is an even worse (or better) example of this non-renewability via dispersion. Of course Helium is inert yet we lose it through the atmosphere.
Ok, so it's ending up in food scraps in land-fills and dissolved into the ocean? I can accept that recovering it from there is unlikely be economic any time soon - although once in the ocean I'd guess it much of it eventually gets absorbed by organisms.
At worst though it would seem that declining reserves of natural high-concentration mineable phosporous will force us to change our agricultural and food-disposal practises to ensure it never gets wasted. Phosporous availability might also present an upper limit on the total amount of biomass (including us humans) the Earth can support, although I would hope our numbers never get high (as it would imply total destruction of most of the non-human biomass first).
This is one reason we ought to be pushing terra preta very hard. We need our farmland to be sponges for phosphorus, so that we do not have to replenish it due to runoff. Fix the cycle to return the phosphorus removed with the crops, and the problem becomes much, much smaller.
This is one reason we ought to be pushing terra preta very hard.
From:
http://ergosphere.blogspot.com/2005/09/scribblings-for-september-2005.html
But riding my hobby horse for a bit... 30 million tons of biomass with 30% conversion to char would make 9 million short tons of charcoal. If each pound of char can make 5.448 lb of zinc metal and you can get 423.6 Wh/lb out of the zinc, you'd get 41,500 million kWh out of it. That's better than 45% of requirements.
Did you have a point to make? (FWIW, I'm now leaning much more toward Li-ion than Zn-air; Zn-air's advantage is the option to refuel rather than recharge and have energy storage outside the vehicle, but Li-ion is now roughly equal in the quick-charge race and the efficiency is higher.)
Did you have a point to make?
If anyone ELSE is interested in 'the point', they can ask, because it strikes me that it is obvious to the most casual observer.
Ok, so it's ending up in food scraps in land-fills and dissolved into the ocean?
'worse' than that. We take the concentrated source (urine at a gram or so a day) http://www.webmd.com/a-to-z-guides/Phosphate-in-Urine and mix it with 1.6 to 5 gals of water per flush. So if 'we' wanted to separate the biologically 'reusable' from the common sewage stream - it somehow has to be 'dewatered'.
To 'recapture' that from urine using a 'low tech' level needs urine that has 'aged', heat to make it a paste (that part could be done with a solar still), then heat the paste with sand so the sodium becomes bonded with the sand and you get the volatile white Phosphorus. Somehow people keeping buckets of aged urine about isn't gonna have alot of buy-in, nor is taking that smelly aged urine and placing that in shallow solar stills gonna be a popular choice of action. Mucking the dried urine into collection containers so the heavy metals, sodium, and whatever else is deemed 'bad' can then be separated from the 'good' again sounds like a hard sell.
From the solid matter side of things - the Worm Gin looks to be one of the best ways to manage worms/waste. South Korea had one that would handle 35 TONS of organic material a day and needed $15 of electricty a day to run the motors.
This is the only reference on the public internet I can no find. http://64.233.167.104/search?q=cache:oNU3jBwXPZgJ:ekoprodukt.ru/obzor_en...
And again, the waste system would have to go from the present 'flush and forget' personal responsibility model to one where fecal matter is not 'diluted' so it can be processed via composting. I do not picture alot of buy-in with such a plan. Some people have already started http://www.thepeacock.com/Front_View_of_Rock_House_3.htm but they are an exception.
Well, no, not many people are going to manually manage any sort of urine (or fecal) drying process - but why can't it be done at a sewage plant?
BTW, I wonder how much phosporous goes to waste in conventional disposal nappies/diapers. Doesn't seem much chance of ever recovering that. But biodegradable nappies could in principle solve that problem...as I understand it they're directly compostable. I'm going to have to look out for some next time we need supplies - I hate disposing of nappies along with household rubbish.
but why can't it be done at a sewage plant?
Think about the water added to the process, then about the ways one can take a watery mix of material and process it. Then add to that watery mix things like oil, paints, paint bush cleaners, medical pills, et la.
BTW, I wonder how much phosporous goes to waste in conventional disposal nappies/diapers.
The Phosphorous cycle in humans has not been a concern for study except for disease. In the limit search on that front I could not find data on the amount in fecal material.
I just returned from a family gathering to find 101 comments under the peak phosphorus article. Thanks for your feedback and suggestions. There's much to chew over. I hope that Patrick Déry, the main author, will be available to respond to the technical points.
Could I make some comments about the framing of the issue? Just as with peak oil, I think there is a danger of getting hung up on the technical details -- the precise date of the peak, the necessity for multiple lines of argument, consideration of specific technologies and reserve estimates. These matters are all important to get the science right. However they are not crucial for making the case that we have a major problem.
As far as I know, no one has disputed the most important points:
These widely accepted points make a prima facie case for peak phosphorus representing a significant challenge for humankind - a challenge that we seem to be ignoring.
Again, thanks to Prof. Goose and TOD for providing the opportunity to publish here, and to you TOD readers for your intelligent responses.
Bart Anderson
Energy Bulletin
PS
TOD member WebHubbleTelescope (WHT) has posted some remarks about the paper on his blog MOBJECTIVIST.
* We currently waste a hell of a lot of phosphorus.
representing a significant challenge for humankind - a challenge that we seem to be ignoring.
'we' are ignoring? This little part of 'we' is not 'ignoring' and I try to keep some of the leakage of Phosphorous to not happen in the form of composting (I will not collect Pee - I lack the money of Huges) - but unlike the end of cheap oil and the societal spasms, issues of potable water are more likely to hit my existence before Peak Phosphorus.
Almost every techno-fixer has no realistic answer to the Phosphorus issue - the closest conversation has been 'quick, go into space!'
True, if you ignore the techno-fix proposals to:
Free Energy is here: http://energie.noosblog.fr/perpetuum_mobile/engine_01_11357.html