One fact is clear: Without phosphorus, we cannot produce food. Declining phosphorus will harm the global food supply, thus affecting all our economies. Extraction continues to increase as the human population increases the demand for food, and as we grow more corn for biofuel production. To account completely for the costs of biofuels from crops, you would have to take into consideration its effect of the price of phosphate.
Mining, of course, may have negative effects on the land and ecosystems. For example, in some phosphorus mines, huge pits and waste ponds have scarred the landscape, damaging biologic and hydrologic resources. Balancing the need for phosphorus with the adverse environmental impacts of mining is a major environmental issue. The United States requires open-pit phosphate mines to be reclaimed to pastureland, an additional cost of biofuel production.
Biofuel proponents say that agrifuels can be grown on nonagricultural land—which is to say, land too rough and steep for farming. The trouble is, a lot of this kind of land is now used for recreation—such as hiking, climbing, skiing, and camping—and to provide habitat for wildlife and endangered species, natural ecosystems, and watersheds for streams and rivers that help sustain biodiversity. Thus, using these nonagricultural lands to produce biofuels can only be detrimental to biodiversity. What’s more, land unsuitable for farming edible crops is also unsuitable for farming the same crops for conversion into fuels. Farming steep slopes leads to erosion; and high elevations and poor soil are too unproductive to be economically useful.
Biofuels from lakes and the seas?
It is difficult to make liquid fuels from land plants. First of all, the plants themselves do not produce ethanol directly (or if they do, it’s in very small quantities). Second, a lot of the plant material is not directly convertible. Third, in most cases a lot of energy is spent transporting things to the plants (fertilizers, pesticides, water, farming equipment) and transporting the crop to a factory where the fuel is made. In sum, it is clear that taking cropland away from food production is a bad idea. Thinking back to solar energy, we realize that today’s off-the-shelf photovoltaics are much more efficient than any land plant in making energy available to us.
These reasons are leading people enthusiastic about biofuels to turn to microorganisms, primarily aquatic algae and photosynthetic bacteria, but also to some microorganisms that are just plain good at converting woody tissue—cellulose in particular—to ethanol. The benefits seem great. These microorganisms produce a lot of biodiesel (oils that, like household vegetable oils, can be used directly in diesel engines) or ethanol directly, so we don’t have to expend energy, materials, and time in making the liquid fuel. They can also grow in habitats that do not directly compete with food production. Where waters are polluted by fertilizer and sewage runoff and therefore are high in nitrogen and phosphorus, the algae and photosynthetic bacteria, which now create environmental messes for us, could play the double role of cleaning up the waters and giving us liquid fuels for aircraft, cars, trucks, and ships. This is all the more important because solar and wind produce electricity, which will play a major role in powering increasing numbers of electric cars, trucks, and rail transportation but cannot be used for air travel unless we use it to make a gas or liquid fuel (more about that in Chapter 10, “Transporting Energy: The Grid, Hydrogen, Batteries, and More”).
Biofuels from microorganisms seems likely to give a large energy benefit, rather than being an energy sink or a net energy nothing as is the case with most of the land devoted today to biofuel production from land plants. David Pimentel, the expert on the ecology of agriculture and environmental effects of biofuels, tells me that ethanol from algae appears able to yield 50% more energy than it takes to produce it.42
SunEco Energy, in Chino, California, says that the algae in its 200 acres of aquaculture ponds yield ethanol with an energy content five times higher than the amount of energy used to grow the algae and process it—and the algae is always there. The company says it can produce ethanol for $0.81 a gallon, making it both energy- and cost-competitive, and projects that it can produce 33,000 gallons of what it calls “biocrude” per acre of ponds one foot deep.43 Some of the major oil companies are getting into this game as well. Exxon plans to invest $600 million in an algae project.
One of the most interesting tests of producing algae from biofuels is a start-up involving the Southern Ute Indian Tribe in southwestern Colorado. They are funding and cooperating with Colorado State University Mechanical Engineering Professor Bryan Willson, who founded Solix Fuels. The company has an unusual approach—the algae are grown in bags in water tanks. The idea is to increase yield, but the production requires more energy and material input than other facilities.44
Another interesting development is the discovery of a bacterium that lives in forest soils and decomposes cellulose from the woody tissues of plants, giving off ethanol as one of its major products. The bacterium is known scientifically as Clostridium phytofermentans and more informally as the “Q Microbe,” because it was discovered near the Quabbin Reservoir by Professor Susan Leschine and her colleagues of the University of Massachusetts. They point out that cellulose is the most abundant organic material on Earth. And, of course, it is in many of our wastes—papers, plastics. The Q Microbe has decomposed wood and sugarcane wastes, and Professor Leschine has set up a company, Qteros, which is doing research and development to use this microbe to both decompose wastes and provide ethanol fuel. Although still in its early stages, the work seems promising; once again, as with algae, this bacterium produces a fuel directly and therefore is likely to give a net energy return.45
The bottom line is that biofuels from microorganisms appear to be the most promising of the biofuels derived from organisms grown directly to produce fuel. But a lot of research and development are needed to find out just how productive of energy these can be. Right now, algae production of biodiesel seems to be the best bet for direct biological production of fuels, from both an energy-efficient and environmental point of view.
Are biofuels the answer?
I was recently on a business trip to Hailsham in southern England, about 100 miles south of London, and took a taxi back to Heathrow Airport. We drove through countryside, pastures full of sheep and this year’s lambs, fields glowing bright yellow with this year’s crop of rapeseed. The driver and I began talking about the local agriculture.
“That’s the stuff I’ve been running this Mercedes diesel on for several years,” he told me—“oil from rapeseed.” I thought he meant that the crop was planted with the purpose of converting it into a fuel, but he said no, he’d just been going to the local supermarket and buying bottles of rapeseed cooking oil (marketed in North America as canola oil) and pouring it into the tank. He said he’d been a car mechanic and had read about this in a car magazine. He used new oil because he’d been warned that dirt and other contaminants in old cooking oil might damage his engine. When he took his diesel in for its annual inspection, the mechanic commented on how clean the engine was. “I don’t notice any difference in the power or acceleration,” he told me.
When Rudolf Diesel invented his engine in the late 19th century, he ran it on vegetable oil and thought that would be the fuel for it. This taxi was proof that vegetable oil did work well as a fuel for a diesel engine. So is this one of the best solutions for us?
Biofuels’ effects on the environment
Biofuels can have various negative effects on the environment.
Destruction of soil and water
Let’s start with ethanol from sugarcane in Brazil because that seems to have the best energy efficiency, reportedly between 1.7 and 9. (The low estimate means that the ethanol contained more than 1.7 times as much energy as was used to obtain it from sugarcane, while the high estimate is 1.9 times the energy input.)46,47 The wide range of energy efficiency has to do with estimates of the energy used in transportation—of fertilizers and pesticides to the cropland, sugar to the mills.
Unfortunately, sugarcane is
notorious the world over for being one of the crops most destructive to soil and water, especially polluting water runoff with soil particles, nitrates, and phosphorus, causing many problems downstream. Farming sugarcane erodes soil at more than five times the rate at which soil is being formed naturally in Brazil. It also takes huge amounts of water, especially to wash away soil that clings to the sugarcane. Washing each ton of sugarcane takes 1,900–9,500 gallons of water. Each acre of sugarcane also uses 59 pounds of nitrogen, 47 pounds of phosphorus, half a pound of insecticides, and 2.7 pounds of herbicides.48
Debate over biofuels and greenhouse gas
One of the issues raised all the time about global warming is that it might increase the rate of extinction of species, and that therefore we must deal with global warming directly.49 This has become a major justification for biofuels. But the result is ironic: Land that is habitat for many species, including endangered ones, is being converted to profit-making agrifuel crops with the justification that this is helping the fight against global warming.
For example, in Asia, natural tropical forests are being cut and turned into coconut plantations to produce biofuel from palm oil. The net effect is to increase carbon released into the atmosphere (because deforestation leads to much decomposition of dead plants and organic matter in soils), to increase soil erosion and water pollution, and to destroy habitats for endangered species such as orangutans.50 The environmental organization Friends of the Earth says that as much as 8% of the world’s annual CO2 emissions can be attributed to draining and deforesting peatlands in Southeast Asia to create palm plantations. The organization estimates that in Indonesia alone 44 million acres have been cleared for these plantations, an area equal to more than 10% of all the cropland in the United States, as large as Oklahoma and larger than Florida.51
The bottom line on biofuels’ environmental effects
Rapid, large-scale deforestation to clear lands for biofuel crops, supposedly being done to reduce CO2 releases into the atmosphere and benefit the environment, will actually increase CO2 releases in the next years and decades, contributing to global warming rather than working against it, and increasing the risk of extinctions rather than reducing them. Even where biofuels might give a net energy yield, the environmental costs are too high to justify the production of these fuels, even if the monetary cost were low, which it is not.
Biofuels’ effects on the pocketbook, direct and indirect
We previously talked about farmers feeding their animals trail mix because feedstock crops have been crowded out by agrifuel crops, making feedstock expensive and hard to get. The same thing is true for our own food crops, with scarcity driving up prices. We feel these higher costs directly.
But it is costing us even more than we realize. Biofuels are expensive to produce. The former head of the Malaysian Palm Oil Association, M. R. Chandran, was quoted in the Wall Street Journal in 2007 as saying that crude oil would now have to be as much as $130 a barrel before palm-oil-based biodiesel is competitive.52 Biofuels are therefore heavily subsidized—by our tax dollars.
So why are biofuels so popular?
Subsidies make biofuels seem less costly than they are. They therefore seem attractive, reasonable, and cost-effective. Precisely how heavily they are subsidized is hard to say, because there are so many ways that governments provide financial support for agriculture in general and for biofuels in particular, some direct, some indirect and hard to uncover.
Big ag—corporate agriculture—is accustomed to big handouts and knows how to get them. As an example, a study done by researchers at the University of California shows that federal subsidies for rice totaled $269.5 million in 2002, exceeding revenue to the farmers from direct sales, which were $214.9 million that year. The study concluded that “rice growing in California could not be done without federal subsidies. This is basically a handout program.”53
Subsidies can make crops for fuel more profitable than crops for food. A May 2007 article in the International Herald Tribune stated that “bioenergy crops have now replaced food as the most profitable crop in a number of European countries. In [Ardea, Italy], for example, the government guarantees the purchase of biofuel crops at £22 per 100 kilograms, or $13.42 per 100 pounds—nearly twice the ... rate on the open market last year. Better still, European farmers are allowed to plant biofuel crops on ‘set-aside’ fields, land that EU agriculture policy would otherwise require them to leave fallow to prevent an oversupply of food.”54
In China, where there is a major commitment to developing biofuels, estimates are that the processing of 100% bioethanol costs about $150 per ton, and this does not include costs for purchasing feedstock. Subsidies are high in China—somewhere between $200 and $300 a ton.
If biofuels did not get big subsidies, in most countries few could afford them. In the United States, corn-based ethanol gets $3 billion in federal and state subsidies each year. Without these, corn-based ethanol production would either greatly decrease or stop altogether. Direct subsidies are $1.00 a gallon for biodiesel produced as an agricultural crop directly for use as fuel, and $0.50 a gallon for biodiesel produced otherwise (such as from wastes).55 And these are just the direct subsidies for biofuels. In addition, their production benefits from the elaborate and complex subsidies for agriculture and from a variety of indirect subsidies that are often difficult to learn about and add to the financial balance. For example, in California in the 1980s, the city of Los Angeles was paying about $300 an acre-foot for water purchased from the Colorado River system, but farmers in the state’s great central valley were getting that same water for $1 or $2 per acre-foot. (An acre-foot, the amount of water to cover an acre of land 1 foot deep, is a standard U.S. measure of water quantity.)
Senator John McCain reported about these subsidies, concluding that the cost to produce a corn-ethanol energy equivalent for gasoline was $4.77 per gallon, while the cost to produce a liter of gasoline from fossil fuels was only $1.27 per gallon.56
Federal and state subsidies for ethanol production go mainly to big corporations, not to individually owned farms.57 One of the most careful analyses of agrifuels, by David Pimentel and Tad W. Patzek of Cornell University, determined that “several corporations, such as Archer Daniels Midland, are making huge profits from ethanol production.”58 Furthermore, they estimate that if you include the increased cost of food, “the costs to the consumer are greater than the $8.4 billion/yr used to subsidize ethanol and corn production.” The National Center for Policy Analysis estimated that ethanol production added more than $1 billion to the cost of beef production.59, 60
In sum, subsidies explain the popularity, and profitability, of biofuels. Without government subsidies, biofuels would not be profitable in the United States and many other nations—the cost efficiency would be too low. And in the United States, the primary beneficiaries of biofuel subsidies are large corporations, not individual farmers.
Could great advances be made in biofuels’ energy production?
To answer this, we have to go back to a point made earlier: that photosynthesis is a natural and ancient process “invented,” so to speak, by bacteria and then “borrowed” and “improved” by algae and green plants. It is a way of using solar energy.
The first research project I ever did in ecology dealt with just how efficient natural vegetation could be as energy factories. I studied how much energy the natural vegetation in an old field, abandoned by a farmer only a year earlier, was able to convert to its organic matter compared with the amount of sunlight available. According to ecological theory of the time, natural ecosystems were most productive in their earliest stages, and therefore this abandoned old field should have been tops in storing energy. In fact, however, this mixture of weedy plants stored just a bit more than 3% of the solar energy that fell on the field during the entire year.61 That’s an indication of what can be expected from natural vegetation.
The old saying that it’s hard to improve on Mother Nature is going to be true fo
r biofuels. As amazing as photosynthesis is, it has its limits, and it is unlikely that the net yield from even intense agriculture is going to do better than that old field. Why? For starters, photosynthesis can make use of only a limited percentage of sunlight—enough to cause the photochemical reaction that leads to energy being stored in organic compounds, but not so much that the energy can seriously damage and destroy living cells.
So think about biofuels as a weaker form of solar energy. Its efficiency is going to be not much better than 3% of the sunlight and certainly less than 10%. Contrast that with what we discussed in the chapters on wind and solar. For example, today’s most efficient photovoltaics “fix” 20% of the sunlight—one-fifth of all sunlight that falls on them goes out as usable electricity.
Should biofuels be wholly disregarded?
Despite all the negatives, and because there is plenty of pressure from nations lacking petroleum reserves and from corporations seeking profits from agriculture, it’s a good idea to keep natural vegetation in mind as one possible sustainable approach to biofuels. A study of a natural prairie in Minnesota indicates that fuel made from a mixture of wild plants could yield “51 percent more energy per acre than ethanol from corn grown on fertile land....This is because perennial prairie plants require little energy to grow and because all parts of the plant above ground are usable.”62
Powering the Future: A Scientist's Guide to Energy Independence Page 21