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From page 1...
... Liquid biofuels used for transportation represent just one form of bioenergy, Searchinger noted, but at this point it is the major form. About 40 percent of the U.S.
From page 2...
... The Effect of Biofuels Usage on Carbon Dioxide Levels One of the main reasons that people support the use of biofuels, Searchinger said, is the belief that "when you switch from burning a fossil fuel to burning a biofuel you get some kind of direct greenhouse gas benefit." But, he said, a close examination indicates that this is not the case and that the belief that there is a direct benefit stems from an "accounting error." The belief that burning biofuels contributes less carbon dioxide to the atmosphere than burning fossil fuels stems from the fact that biofuels are derived from plants, which absorb carbon dioxide as they grow. "So, the theory is that, in effect, bioenergy is just recycling carbon, not
From page 3...
... . Thee first few steeps of the production p prrocess for bioffuels always pproduce moree emissions thhan the prroduction pro ocess for gassoline, he saaid, "because it takes moore energy y and emissions to producee the crop andd to transform m it into ethannol than itt does to minee crude oil and d refine it intoo gasoline." T The greenhouuse gases emitted from m the tailpipe of a car are about the saame for ethannol and gaasoline, but th here is a another source oof greenhousee gas emissioons for thee ethanol, wh hich is the ferrmentation proocess.
From page 4...
... "One way to think about it is that if you had a bare piece of land and you allowed it to grow as a forest, that forest would accumulate carbon, and it would reduce greenhouse gas emissions. On the other hand, if you simply had a forest that was growing anyway, you couldn't count that as an offset." Ignoring this basic fact is a fundamental error that often appears in calculating the biofuels offset.
From page 5...
... Similarly, if there is a crop residue, such as rice straw, that would normally be burned but instead is used to make ethanol, that is a legitimate greenhouse gas saving because the usual carbon dioxide emissions from that rice field have been reduced. On the other hand, if one takes a corn crop that would have been grown anyway and simply diverts it for use in fuel, that does not represent a legitimate offset because there is no additional plant growth and no additional carbon dioxide removed from the atmosphere.
From page 6...
... In short, out of the three possible indirect effects of growing corn to produce ethanol, Searchinger said, two are bad. "Land-use change leads to greenhouse gas emissions and habitat loss, and reduced food consumption leads to hunger.
From page 7...
... "Roughly speaking," he said, "this is a 275 percent higher price than the long-term corn price in the first part of the 2000s." Thus, corn prices get bid up until they get close to that level -- and as the price for corn intended for ethanol production increases, the price for corn intended for consumption increases along with it, for the crops are the same. Furthermore, as the price of corn increases, the price of wheat and soybeans -- and, to a lesser extent, rice -- track the price of corn very closely because the crops can, to a significant extent, be substituted for one another.
From page 8...
... "When you compare that to historical growth rates, that means calorie growth would have to grow as much as it did each year during the height of the green revolution, and meat production would have to grow 30 percent higher." Furthermore, even during the green revolution, when irrigation rates doubled and many parts of the world began using fertilizer that hadn't used it before, there was still an increase of more than 400 million hectares of land devoted to crops. "So, the point is that even without an increased demand for crops for biofuels, it will be a very tight challenge to produce all the food we want on the same land," Searchinger said.
From page 9...
... What that means is it takes a tremendous amount of land to make a small amount of bioenergy." The bottom line is that to provide 10 percent of the world's transportation fuel by 2050 would require 36 percent of all of today's crop production, and it would amount to less than 2 percent of the world's delivered energy at that time.
From page 10...
... The bottom line, Searchinger said, is that trying to make energy from crops will drive up food prices and have a major health effect through hunger, while at the same time, because of the issues surrounding changing land use, increasing biofuels production would not actually reduce greenhouse gas emissions. BIOFUELS IN THE CONTEXT OF THE LARGER ENERGY PICTURE In the session's second presentation, Howard Gruenspecht, the deputy administrator of the U.S.
From page 11...
... This decreease in gasolline consumpption is partt of an overrall declinee in energy consumption c by the transpportation secttor, which is in part du ue to the effeccts of the receent economicc downturn, w which has led to a decrrease in vehiccle miles of travel. Anothher factor inn the decline in energy y consumptio on by the tran nsportation seector has beeen the growinng efficieency of the liight-duty veh hicle fleet, whhich has resuulted both froom markett effects and d regulations on fuel econnomy.
From page 12...
... By 2011 ethanol made up more than 9 percent of all gasoline sold by volume, although it represented only about 6 percent of gasoline fuel in terms of energy content. By contrast, biodiesel makes up a much smaller percentage of all diesel fuel sold in the United States -- just fewer than 2 percent both in terms of volume and in terms of energy content.
From page 13...
... Years ago, when customers had a choice between 100 percent petroleum-based gasoline and gasoline containing 10 percent ethanol, their behavior indicated that they generally looked for the cheapest price per gallon without taking into account the lower energy content of gasoline with ethanol. And today it does not matter because nearly all gasoline available at retail outlets contains 10 percent ethanol by volume.
From page 14...
... The renewable fuels standards, which were enacted in the Energy Policy Act of 2005 and expanded by the Energy Independence and Security Act of 2007, set a series of annual targets for various groups of biofuels. "The number that people remember," Gruenspecht said, "is the 2022 number for total biofuels, which is 36 billion gallons, of which 21 billion falls in the category of advanced biofuels, with 16 billion of that 21 billion falling in the advanced fuels subcategory of cellulosic biofuels." To date, he added, there has been little success in producing cellulosic biofuels, and the EPA has ended up modifying the statutory goal in each of the years through 2012.
From page 15...
...  Natural gas production grows faster than in previous projections, serving the industrial and power sectors and an expanding export market.  Motor gasoline consumption reflects the introduction of more stringent fuel economy standards, while diesel fuel consumption is moderated by increased natural gas use in heavy-duty vehicles.
From page 16...
... Reenewables are predicted to t meet a larrge share off the growth in energyy use. Much of that grow wth is expec ted to come in renewablles (excluding liquid biofuels)
From page 17...
... Similarly, the cellulosic biofuels are projected to fall far short of the 16 billion gallons called for in the federal legislation; according to the projections far less than 1 billion gallons of cellulosic biofuels will be used in 2022. However, Gruenspecht said, "As the price
From page 18...
... . and as technology improves, we do expect more biofuels to come in." According to the projections, by 2040 more than 25 billion ethanol-equivalent gallons of biofuels will be used, including some 9 billion gallons of cellulosic biofuels.
From page 19...
... By contraast, the resst of the world is expectted to grow substantially in populatioon, global energy demaand, and enerrgy consumpttion. Still, Prrince said, theere will bee huge amou unts of energy y saved over what would normally haave been expected becau use of the effiiciencies that are coming innto the markett.
From page 20...
... Renewables make up a relatively small part of the overall energy mix, and the category of "wind, solar, and biofuels" makes up a very small part of the renewable energy mix. Thus, despite recent efforts to increase the amount of renewable energy produced, Prince said, renewables still make up only a tiny sliver of the world's overall energy budget.
From page 21...
... The study assumed that sharp increases in energy efficiency and decreases in demand per capita can be achieved in the next 70 years, but that still left a rapidly growing need for energy produced with little or no greenhouse gas emissions, such as nuclear power, fossil fuel plants with carbon capture technology, and renewables. There is tremendous public support for bioenergy to be a large part of that renewable energy segment, Prince said.
From page 22...
... It's an interesting question as to how long one can continue doing that." There are efforts under way to use no-till farming to reduce the soil loss, but their widespread adoption is still uncertain. A positive factor is that the major byproducts of converting corn into ethanol are used as animal feed.
From page 23...
... As with ethanol production from corn, a byproduct of biodiesel production from soybeans can be used as animal feed, and it plays an important role in the economics of biodiesel production. And as with ethanol production, there are serious problems of soil erosion that accompany the production of biodiesel.
From page 24...
... Today, they can get $200 a ton for hay." Given the difference, it is unlikely that many farmers will switch over from hay to cellulosic biomass. Looking ahead, Prince said that there are a number of bioenergy pathways emerging -- ways in which bioenergy could contribute to the overall energy supply.
From page 25...
... The use of ethanol as a volume enhancer in fuel has not been driven by the mandates, either, he said, but it has been driven by the existence of the tax credits for producing ethanol from corn. "People were looking for the cheapest volumes, and with the tax credits on a volume basis the ethanol was cheaper, so retailers and distributors were happy to put as much of ethanol into the fuel as they could, which was that 10 percent blend wall," Gruenspecht said.
From page 26...
... The literature clearly indicates that biofuels production has had some effect, "but there also have been some important droughts, and there have been some very bad policies that foreign governments have undertaken in response to price increases, such closing markets, which actually aggravated it." More broadly, she said, it is important to look carefully at the connection between ethanol production and food prices and also the connection between food prices and health. First, she noted, "Corn went from $4 in 2007 to about $7 now.
From page 27...
... 2005. Sequestration of fermentation CO2 from ethanol production.
From page 28...
... Presentation at the Institute of Medicine Workshop on the Nexus of Biofuels Energy, Climate Change, and Health, Washington, DC.


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