In general, corn production is a frequent source of nutrient and sediment pollution. Another debate about corn and soy-based biofuels concerns the amount of land it takes away from food production. The challenge of growing enough crops to meet the demands of ethanol and biodiesel production is significant and, some say, insurmountable. Brown is an energy consultant and former energy program director at the National Conference of State Legislatures. Also, when considering the implementation of ethanol, it must be noted that biofuels aren't meant for all vehicles, especially older ones.
One solution to this has been the introduction of flexible fuel vehicles. These have the advantage of being able to use E85, gasoline, or a combination of the two and give drivers the flexibility to choose the fuel that is most available or best suited to their needs.
Still, there is some resistance from the automotive industry when it comes to adding biofuels like ethanol to the market. E85 FlexFuel. Department of Energy. Hoffman, William, and Leo Furcht. The Biologist's Imagination: Innovation in the Biosciences.
Oxford University Press, Sandhu, Harpinder, et al. Pimentel, David, and Tad W. And because the EPA tends to grant the small-refinery exemptions in batches in August of this year it granted 31 of them , the exemptions drive RIN prices down.
Angry corn producers then besiege the White House with an army of hired lobbyists and members of Congress, demanding that the EPA allow the sale of higher-percentage ethanol blends and promulgate a higher overall target-volume RFS.
As a result of these opposing forces, the government oscillates between helping refineries and helping corn producers, in a pattern that has been almost perfectly continuous since the Obama administration first exercised the refinery exemptions, in Ethanol mandates are a marvelous candidate for deregulation—but they are caught in the middle of such a withering cross fire of special-interest groups that nobody in the White House wants to touch the issue with a foot pole, as I saw firsthand during my years there.
The sale of E15 may create a backlash once the public learns about the downsides of higher ethanol blends, especially for older vehicles. Moreover, the problems of the RIN market are not endogenous to that market; they are created by the underlying RFS program, and a higher-volume RFS will make those problems worse.
A major study by the National Academies of Sciences found that biofuels can be cost-competitive with fossil fuels only in an economic environment of high oil prices. In fact, perversely enough, the RFS expands the supply of gasoline, thereby helping keep fossil-fuel prices low in the long run. The single biggest obstacle to a completely carbon-free future is the fact that automobiles, airplanes, and ships are tethered to oil as an energy source—whereas almost everything else that consumes energy just needs to connect to the electricity grid.
If federal officials ever got serious about climate change and facilitated rapid deployment of nuclear energy, electricity production could be down to zero carbon emissions within a decade or two. By expanding the supply of gasoline, the RFS program helps ensure that gasoline-powered cars remain on the road longer. Cheap gasoline is nice in the short term, but in exchange for that, the RFS gives us more expensive food.
In the United States, the cultivation of corn for ethanol now requires a staggering 38 million acres of land—an area larger than the state of Illinois.
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Oon and Samira Gharehkhani. From the journal Reviews in Chemical Engineering. Cite this. You currently have no access to view or download this content. Please log in with your institutional or personal account if you should have access to this content through either of these. Showing a limited preview of this publication:. Abstract Biofuels are acting as a renewable replacement for petroleum fuels due to some environmental and economic benefits. Keywords: biofuel ; emission ; environment ; ethanol ; food chain.
Second, the higher the price of oil, the more economically ethanol can be blended with gasoline. When corn is cheap and oil prices are high, ethanol margins are fat. But when corn prices rise and oil prices fall, ethanol margins are flat.
As ethanol production took off in the mids, aided and abetted by a panoply of federal and state subsidies, it chewed up so much corn so fast that it was hoisted on its own petard as corn prices rose to record highs in while oil prices weakened. Corn prices then fell back as farmers responded to high prices with record plantings. Today, oil prices remain low and corn prices are strengthening again. Despite recent weakness, corn prices remain nearly double their level of when the major elements of ethanol subsidies and mandates began to be put in place.
In the face of these tribulations, the revisionist ethanol narrative makes a number of shaky assumptions. To date, ethanol has been antithetical to fuel economy.
According to the U. Advocates of E30 argue that such inefficiencies can be overcome if high-compression engines are tuned to use the fuel and are certified under EPA rules, making such engines more akin to racecars. But this would mean further EPA regulatory backing for E30 to assure its availability. A key argument of E30 proponents is that higher-ethanol blends would reduce the need for alternative fuel additives that may have negative health effects. In support, they cite studies related to the impacts of aromatic hydrocarbons from gasoline additives used to boost octane, which lead in turn to secondary particulates with impacts on human health.
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