Since that time, The Energy Independence and Security Act of signed by President Bush requires renewable fuel usage to increase to 36 billion gallons annually by Renewable Fuels Association, b. The new RFS which currently guides national ethanol policy states that only 15 billion gallons of production should be produced from corn grain starch —the remaining 22 billion should come from other advanced and cellulosic feedstock sources.
Bevill, K. Department of Agricultural and Biosystems Engineering. NDSU Extension. Energy Accessibility. A nonprofit, independent media organization dedicated to telling stories of climate solutions and a just future.
Grist thanks its sponsors. Become one. So … what is it? E85 is a motor fuel that is a blend of 15 percent unleaded gasoline and 85 percent ethanol, by volume. In the U. The U. Why should I care? Proponents of E85 emphasize that it burns nearly 30 percent cleaner than gasoline. Compared to gas-fueled vehicles, vehicles running on E85 emit about the same amount of nitrogen oxides, the same or lower levels of hydrocarbon and non-methane hydrocarbon, and less carbon monoxide and carbon dioxide.
Ethanol can also be produced from domestic crops, boosting the U. And, say boosters, demand for E85 will encourage the growth of more crops, which suck up CO2. Sounds great. What could go wrong? Naysayers naysay that, this being the U. Large-scale plantations will likely require lots of genetically modified seeds, pesticides, and nitrogen fertilizer. This act provides credits for the production of vehicles that run on alternative fuels.
As It Still Runs points out, the use of ethanol blends such as E85 can reduce greenhouse gas emissions. As ethanol crops grow, they capture CO2. Ethanol blends provide improved combustion, which releases fewer pollutants. Using E85 also means drivers use less oil. While E85 often reduces an automobile's mile-per-gallon rating by 25 to 30 percent , it can increase the vehicle's power and performance. Car Talk states that, even though some vehicles can't run on E85, flex fuel has become more popular in the United States, especially in the Midwest.
E85 contains up to 85 percent ethanol, which is a grain alcohol usually made from corn. Some producers also use cane sugar or agricultural waste products to produce ethanol. He also produced a Model T that could run on ethanol or gasoline. Manufacturers are still refining flex-fuel technology more than a century later. While some consider E85 to be environmentally friendly, not all environmentalists support the use of corn-based ethanol. His analysis of the economic and environmental impacts of ethanol production found it underwhelming in both aspects.
A study released by the U. Department of Agriculture USDA finds greenhouse gas emissions from corn-based ethanol are about 39 percent lower than gasoline. The study also states that when ethanol is refined at natural gas-powered refineries, the greenhouse gas emissions are even lower, around 43 percent below gasoline. Car Talk notes that, in the past, manufacturers receive financial incentives from the government to produce flex-fuel vehicles.
These credits allow a manufacturer to sell less fuel-efficient but more profitable SUVs without receiving a federal penalty. Some engineers we interviewed say E85 fuel economy could approach that of gasoline if manufacturers optimized engines for that fuel, however. For decades, the federal government has promoted ethanol as a renewable, homegrown alternative to gasoline in three distinct ways.
Proponents see this support as necessary to get the alternative fuel into widespread availability and usage. The first effort to support ethanol usage is a cent-per-gallon tax credit to "blenders," the companies who blend ethanol into gasoline. This tax credit is intended to raise the price of ethanol for ethanol producers and corn farmers to encourage production, and to lower the price of ethanol products for consumers.
It is strongly supported by farm lobbyists. Despite the tax credit, however, E85 costs about 70 cents a gallon more than gasoline on an energy equivalent basis on average, according to the Department of Energy.
Second, the government provides significant fuel economy credits to automakers who build flex-fuel vehicles that can run on E Under the regulations, the average fuel economy for an automaker's entire fleet of vehicles must meet a minimum miles-per-gallon figure: So the more large vehicles a manufacturer builds with gas mileage below that minimum, the more they have to be offset either by smaller vehicles that get better fuel economy or by fuel-economy credits, such as the one for FFVs.
This is quite literally a loophole big enough to drive a truck through for automakers that produce many gas-guzzling pickups and SUVs. The FFV credit was intended to provide an incentive to get E85 vehicles on the road. In determining the credit, the government assumes that an FFV will run on E85 half the time and on gasoline the other half.
For CAFE purposes, the E85 half is calculated as using only the 15 percent of the fuel that is gasoline. So the government rates FFVs at about 1. This applies to the Tahoe we bought in New England even though we couldn't find any E85 to use in it near us. The maximum that an automaker's fleet average can be raised because of FFV credits is 1. Of the 13 billion gallons of ethanol expected to be produced in and , less than 2 percent, or million gallons, will be blended into E Because our tests show that E85 provides 27 percent lower fuel economy, those million gallons are able to replace only a little more than million gallons of gasoline—a tiny fraction of the billion gallons consumed on American roads every year.
While the credits have put millions of FFVs on the road since the late s, most have been large SUVs, pickups, and sedans that get relatively poor gas mileage and don't do well in Consumer Reports testing.
In the end, these FFV credits have indirectly allowed more large, gas-guzzling vehicles to be sold. As a result, these credits have increased annual U. The third government initiative to promote ethanol is a mandate Congress passed as part of the Energy Independence and Security Act of requiring refiners to blend up to 36 billion gallons of ethanol into gasoline by Increasing ethanol penetration much beyond current production will require either expanded sales and distribution of E85, or greater concentrations of ethanol in base gasoline.
Automakers say this would essentially require all cars to be flex-fuel vehicles. From an alternative-energy perspective, it doesn't matter in what proportions ethanol is blended.
Whether mixed in E85 or E10, a given amount of ethanol still goes just as far in reducing demand for gasoline. Ethanol advocates' latest gambit is to increase the percentage of ethanol blended into gas for regular cars from 10 percent to 15 percent. And Underwriters Laboratories certified regular gas pumps to dispense ethanol blends up to 15 percent. Furthermore, energy experts at Argonne National Laboratory say that corn production can't be expanded enough to produce more than about 15 billion gallons of ethanol.
So to meet the billion-gallon mandate will require new sources of ethanol. The government also says corn is not a good long-term fuel source because it diverts corn from the food supply. Most experts don't see the future of the ethanol industry taking root in America's cornfields.
A more promising long-term solution is cellulosic ethanol, which can be made from a variety of other sources such as corn stover leaves, stalks, and other leftover parts , rye straw, wood pulp, and possibly switchgrass commonly used for hay.
In Brazil, where every new car runs on at least percent ethanol and many run on pure ethanol, the fuel is made from sugarcane. A study conducted by the U. Department of Agriculture and Oak Ridge National Laboratory estimates that by , ethanol from corn and cellulose could replace 30 percent of U.
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