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By 2050, the global population will hit between 7.5 billion and 10.5 billion. Energy demands will soar, and traditional energy supplies, such as petroleum, will struggle to meet the demands. Biofuels will be essential “for future fuel solutions that are affordable, available, and clean,” says Arthur Reijnhart, general manager of alternative energies and fuels development strategy at Shell.
Belief in the ability of biofuels to solve our transportation energy needs goes as far back as 1925 when automobile pioneer Henry Ford said in an interview with Christian Science Monitor: “The fuel of the future is going to come from fruit like that sumac out by the road, or from apples, weeds, sawdust—almost anything.”
Over the past decade, more than 50 countries, including the U.S., have been scurrying to implement policies to integrate biofuels into the transportation infrastructure in the face of a number of pressing needs—national energy security, a sustainable agricultural sector, job creation in the rural economy, and reduction of carbon dioxide emissions to curtail climate change. Producing fuel crops that would meet a country’s domestic fuel needs, revitalize rural economies, and cut down on greenhouse gas emissions appeared to be a one-size-fits-all solution.
With experience and hindsight, experts are taking a more measured view of biofuels and their promise to be affordable, available, and clean. Among the factors under scrutiny are raw materials, environmental impact, social cost, and infrastructure implementation.
“We don’t believe that [biofuels] will be the silver bullet solution, let’s be clear about that,” Reijnhart stresses.
First generation: Ethanol and biodiesel are commercially available first-generation biofuels. Ethanol comes from the starches and sugars in food crops such as corn and sugarcane. Sugarcane is a more efficient source than corn and the one on which Brazil, which is second to the U.S. in producing ethanol biofuel, has built its biofuels industry. The U.S. ethanol industry largely rests on corn. First-generation biodiesel mostly comes from rapeseed (canola), but soy and palm also contribute. According to biofuels expert Anselm Eisentraut at the International Energy Agency, ethanol from corn and sugarcane can “be produced at prices competitive with fossil fuels today.”
Second generation: Experts believe cellulosic ethanol made from inedible plant matter, such as switchgrass and wood trimmings, will be the next type of biofuel to enter the market. Its advantage is the feedstocks can be more environmentally friendly and economically sustainable than food-based biofuels. The biggest technical challenge, however, is economically converting molecules in plant cell walls into biofuels. It’s a challenge where “there’s a huge potential for chemical engineers to contribute” to bring down costs of processing, points out Alena Buyx, assistant director of the secretariat at the Nuffield Council on Bioethics, a U.K.-based think tank. Biodiesel also is a second-generation biofuel when it’s produced from plant matter by a variety of methods. The most famous one—Fischer-Tropsch synthesis—converts a mixture of carbon monoxide and hydrogen into liquid hydrocarbons; it was used by the Germans during World War II to produce petroleum substitutes.
Third generation: This generation of biofuels is sometimes referred to as the “advanced” generation. Fuels in this category are generally oils, such as jet fuel, derived from algae and other aquatic species. The hydrocarbon molecules in these fuels often pack more energy per gallon than do first- or second-generation biofuels. Like second-generation biofuels, the third generation of biofuels aims to not compete with food for land; to not harm the environment; to have high energy yields with low inputs of water, land and fertilizer; and to have cost-effective production.
It’s becoming clear that biofuels will not solve all the problems proponents had hoped they would solve, but many countries are still rushing headlong as though they will, with policies that, experts say, are doing both harm and good. Governments need to pause, step back, and take a more nuanced and sophisticated view of biofuels, taking into consideration their sustainability and social costs, explains Alena Buyx, the assistant director of the secretariat at the Nuffield Council on Bioethics (NCB), a U.K.-based think tank.
Driving the U.S. biofuels market is Renewable Fuel Standard 2 (RFS2). Originally created under the Energy Policy Act of 2005 and expanded into RFS2 in 2007 under the Energy Independence & Security Act, the mandate is being implemented by the Environmental Protection Agency. Among other things, RFS2 calls for the blending of 36 billion gal of renewable fuel into transportation fuel by 2022 to reduce foreign oil imports and greenhouse gas emissions.
“The biofuels business globally would not exist if it weren’t for the mandates,” Reijnhart states. Like the U.S., many countries have implemented a blending mandate, defining the percentage of biofuel that must be used in lightweight vehicle fuel. Most engines in lightweight vehicles can’t use pure ethanol or biodiesel because of technical limitations, but they can take them in blended form, such as at a 10% mix with petroleum-based fuels (see page 26). Thanks to the policies, global biofuel production has gone from about 4 billion gal in 2000 to more than 26 billion gal in 2010, Anselm Eisentraut, biofuels expert at the International Energy Agency, says.
So-called first-generation biofuels—ethanol from corn or sugarcane and biodiesel from rapeseed, soy, or palm oil—are meeting many of the mandates. But an NCB report on the ethics of biofuels production released last April acknowledges that in the rush to meet mandates, the large-scale production of first-generation biofuels presents problems. The report explores and finds instances of infringement of the rights of farmers, farmworkers, and landholders, especially in parts of the developing world. It also finds that some first-generation biofuels have severe environmental consequences, including pollution and the loss of biodiversity.
The report urges more R&D into next-generation biofuels that avoid harmful consequences. “What can be said with confidence is that the lessons learned from the problems of established biofuels must be integral in the development of new ones in order not to repeat the mistakes of the past,” the report states. It adds that first-generation biofuels have to continue to meet targets set out in mandates but their negative effects need to be reined in. The report provides an ethical framework to evaluate biofuels and help the direction of future policy development.
Biofuels expert Sébastien Haye, manager of environmental affairs of the Roundtable on Sustainable Biofuels (RSB), headquartered at the Swiss Federal Institute of Technology, in Lausanne, echoes the report’s findings. RSB has 130 members from government, nonprofit organizations, and industry from more than 35 countries.
“If you set targets of reaching a certain percentage of biofuels within a certain time, you have to make sure you are able to supply these volumes in a sustainable manner,” Haye says. Global targets of using a certain amount of renewable fuels by a date that’s soon coming up, he says, unwittingly create “a driver for a very intensive production of biofuels, which increases the risk that the production is unsustainable.”
Unsustainable production is exactly what is happening in the U.S., according to Barbara Bramble, senior program adviser for international affairs at the National Wildlife Federation, a conservation group. She likens the current state of federal policy on biofuels to “a heavy foot on the accelerator of the car without really knowing where we’re going.”
Sustainability, however, was not the overwhelming consideration when current federal policy on biofuels, embodied in the Energy Independence & Security Act, was crafted. When policy was established to blend up to 15 billion gal of corn-based ethanol into gasoline, it was done mainly to accommodate the overwhelming yields of corn, Bramble explains. Corn-based ethanol currently meets 10% of the U.S.’s transportation fuel needs—or 13 billion gal per year.
But as the NCB report notes, experts have some concern that corn is a highly inefficient biofuel source with severe environmental consequences. The crop needs huge amounts of pesticides and fertilizers, which require fossil fuels for their production. The fertilizers exacerbate the environmental damage when they run off the fields, which are concentrated in the central U.S., and into the rivers, eventually causing dead zones in the Gulf of Mexico, according to Kenneth B. Medlock III, an economist with the James A. Baker III Institute for Public Policy at Rice University.
Others also blame corn for cramping the development of other biofuels in the U.S. “If we weren’t using so much corn, other feedstocks would have an opportunity” to develop, Bramble says. “A sad impact is that we have so much corn that it crowds out the space for [next]-generation biofuels. Who would want to go out on a limb to develop more difficult technologies when corn is so easy?”
A White House Twitter town hall meeting in July picked up on that sentiment. At that meeting President Barack Obama said, “I’m a big supporter of biofuels. But one of the things that has become clear is that we need to accelerate our basic research in ethanol and other biofuels that are made from things like wood chips and algae as opposed to just focusing on corn, which is probably the least efficient energy producer.”
Without the strong push for corn by interested parties, corn supporters note, biofuels would not be in the market today. “If we didn’t have the power of the corn-state lobby to help balance the power of the oil-state lobby, we would still be stuck with 100% petroleum fuels and we’d have even higher fuel prices because there would be no competition,” says Bruce Dale, a chemical engineer at the Department of Energy’s Great Lakes Bioenergy Research Center at Michigan State University. “At least now we have some competition in part of the fuel market.”
It’s not as if the current federal policy is oblivious to other forms of biofuels. In fact, it carves out a niche for them, points out William F. Hagy III, director of alternative energy policy at the Department of Agriculture. RFS2 demands that of the 36 billion gal of renewable fuel in the transportation fuel infrastructure by the year 2022, “only 15 billion,” he says, “can come from the corn kernel starch. The other 21 billion must come from other types of alternative fuels.”
How to get that 21 billion gal remains a question. Most next-generation biofuels haven’t even gotten as far as demonstration-phase facilities and remain laboratory-scale research projects. Their slow development is evident in recent implementation of RFS2. In 2007, the mandate called for 250 million gal of cellulosic ethanol to be produced in 2011 and for 500 million gal in 2012. But EPA has reduced the cellulosic mandate to 6.6 million gal for 2011 and is proposing to require only 3.5 million to 12.9 million gal for 2012.
Experts agree that government support, in the forms of funding and policies, is sorely needed to get cellulosic and other advanced biofuels into the market, much in the same way that governments stepped in to help first-generation biofuels. The policies will have to set up ways to get the market to expand so that consumers can demand more biofuels. “The more ethanol the country demands, the more private market investment will go into cellulosic ethanol,” says Christopher Thorne, public affairs director of Growth Energy.
Growth Energy, a trade organization that represents U.S. ethanol producers, holds cellulosic ethanol, a second-generation biofuel, in high regard, calling it “the 50-state solution.” “Every state has some form of cellulosic biomass that could be converted into ethanol,” Thorne says. But cellulosic ethanol currently faces a bumpy road to commercialization (C&EN, Sept. 13, 2010, page 20), with R&D projects still mostly in laboratories. “Taking [a process] from a petri dish level and putting it into 50-gal-drum level of production is a vastly different and extremely expensive enterprise,” Thorne says.
Government action may help. DOE recently gave cellulosic-ethanol producer Poet a conditional $105 million loan guarantee to build the first U.S. commercial-scale cellulosic-ethanol plant. “We feel it’s appropriate for the government to assist in getting those pioneer plants built and running so that the marketplace can then see a reduced risk level and help make private investment flow,” says Paul Bryan, director of DOE’s Biomass Program.
Regardless of the source, infrastructure needs to cope with the increased amounts of ethanol in the transportation fuel system. For instance, right now, ethanol is transported by tanks, barges, and trucks to consumers. But for it to become more pervasive in the market, dedicated ethanol pipelines will be needed; existing pipelines, as well as gas pumps, can’t be used because ethanol damages them.
Along with Thorne and Dale, Robert E. Kozak agrees that the fuel infrastructure isn’t an insurmountable problem. Kozak is president of Atlantic Biomass Conversions, a group doing research in advanced biofuels. They say it’s a matter of implementing policies to install pipelines and pumps compatible with ethanol and to adopt flexible-fuel vehicles, which have special engines that run on 85% ethanol.
Furthermore, as USDA’s Hagy points out, cellulosic biofuels can be produced locally, thereby “eliminating a lot of the transportation issues up front because the feedstock is grown normally [within a] 50- to 100-mile radius of the biorefineries,” he says. “There is no need to transport the finished product over large distances.”
So-called drop-in biofuels would also alleviate the infrastructure problem. Drop-in biofuels are fuels containing hydrocarbons identical to those in petroleum-based gasoline. Their allure is that they can be processed in existing refineries and introduced into existing distribution infrastructure without any modifications. They can even go into boats and lawn mowers. DOE is supporting work to convert animal fats or vegetable oils to drop-in fuels.
Beyond infrastructure, biofuels will still face problems, such as the food-versus-fuel controversy. The most recent flare-up happened in 2008, when biofuels were fingered as the cause of rising food prices. NCB’s Buyx and others point out in various analyses that biofuels appeared to be only one of several factors in changing food prices. High energy prices and a weak dollar seemed to have been more significant.
The food-versus-fuel controversy also questions the use of agricultural land to grow biofuel raw materials. Experts note, however, that agricultural land need not be affected by biofuel production because DOE and USDA have been promoting cultivation of energy crops on marginal land that does not support agriculture.
Furthermore, others emphasize that more than 80% of arable land in the U.S. goes to producing feed for livestock, not growing food for humans. “All the sweet corn that you see on the table is less than 1% of the corn grown in this country,” Thorne states.
With so much land devoted to raising livestock feed, Kozak says, the focus should be on fuels and feed. Animal feed is a lucrative business for the U.S., with China importing it at rates of up to 50 cents a lb. If methods can be developed to break down plant cell walls to get the sugars for biofuels while saving the proteins for animal feed, Kozak notes, biofuel sources such as corn can provide fuel and feed. “We have to start looking at biofuel production in the context of it being a dual use,” Kozak says.
As for the concern that biofuels are not as kind to the environment as previously believed, several experts say that for a fuel to qualify as an advanced biofuel under the RFS2, the production, life cycle, and all other aspects of the fuel must achieve at least a reduction of 50% in greenhouse gas emissions. “The environmental aspects are being responded to up front,” Hagy states.
To ensure that biofuels don’t cause more harm than good, RSB has developed a voluntary standard and certification system for sustainable biofuel production that the European Union has now recognized. The standard requires the entire biofuel production chain to meet various environmental and social criteria, such as reducing greenhouse gas emissions and not damaging lands with great biodiversity. Biofuel producers will seek RSB certification, Haye explains, to get a stamp of credibility and gain acceptance in markets.
Going forward, Dale says, analyses of biofuels and their effects have to be more thorough to understand in detail their impacts on society and the environment. For the sake of accurate and fair analyses, he emphasizes, the consequences of biofuel production—on the environment, society, or technology—must always be compared with those of fossil-fuel production. If people want to continue to drive and fly and, simultaneously, reduce fossil-fuel consumption, increase national energy security, and mitigate climate change, biofuels are the only option for the immediate future, experts agree. Policies already reflect their importance for a sustainable transportation sector, but policymakers now need to consider the nuances of their production. Dale states, “We need to figure out how to produce biofuels correctly and then go do it.” ◾
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