<<For one thing you've got it backwards. Bush is trying to force California to use more polluting ethanol. I've read that several times. >>
Yes, Bobby Redfern and Mrs. Brolin say ethanol pollutes. However-
Ethanol is one of the best tools we have to fight air pollution from vehicles. Ethanol contains 35% oxygen. Adding oxygen to fuel results in more complete fuel combustion, thus reducing harmful tailpipe emissions. Ethanol also displaces the use of toxic gasoline components such as benzene, a carcinogen. Ethanol is non-toxic, water soluble and quickly biodegradable.
Ethanol is a renewable fuel produced from plants, unlike petroleum-based fossil fuels that have a limited supply and are the major contributor of carbon dioxide emissions, a greenhouse gas.
The ethanol production process represents a carbon cycle, where plants absorb carbon dioxide during growth, "recycling" the carbon released during fuel combustion.
Ethanol is one of the best tools we have to fight air pollution from vehicles. Ethanol contains 35% oxygen. Adding oxygen to fuel results in more complete fuel combustion, thus reducing harmful tailpipe emissions. Ethanol also displaces the use of toxic gasoline components such as benzene, a carcinogen. Ethanol is non-toxic, water soluble and quickly biodegradable.
Ethanol is a renewable fuel produced from plants, unlike petroleum-based fossil fuels that have a limited supply and are the major contributor of carbon dioxide emissions, a greenhouse gas.
The ethanol production process represents a carbon cycle, where plants absorb carbon dioxide during growth, "recycling" the carbon released during fuel combustion.
The use of grain-based ethanol reduces greenhouse gas emissions 35-46% compared with conventional gasoline. Biomass ethanol provides an even greater reduction.
The American Lung Association of Metropolitan Chicago credits ethanol-blended reformulated gasoline with reducing smog-forming emissions by 25% since 1990.
Ethanol reduces tailpipe carbon monoxide emissions by as much as 30%.
Ethanol reduces exhaust VOC emissions by 12%.
Ethanol reduces toxic emissions by 30%.
Ethanol reduces particulate emissions, especially fine-particulates that pose a health threat to children, senior citizens, and those with respiratory ailments.
Ethanol is widely used in the federal winter oxygenated fuels program and the reformulated gasoline (RFG) program in cities that exceed public health standards for carbon monoxide and ozone pollution.
Don't new cars have emissions control systems that make the addition of oxygenates like ethanol to gasoline unnecessary?
No. While cars produced since 1996 have improved pollution controls, ethanol still has a vital role to play in keeping our air clean. Over half of the air pollution attributable to vehicles comes from "high emitting" vehicles that make up only 10% of the vehicle fleet. High emitters include older vehicles as well as well as newer cars with malfunctioning pollution control systems. The use of ethanol-blended fuel is also one of the best pollution control strategies for off-road vehicles, including motorcycles, ATVs and snowmobiles, which represent a significant source of emissions.
I'm concerned about gasoline components leaking into the water supply. Will ethanol harm our water?
No. Ethanol is the safest component in gasoline today. Ethanol is rapidly biodegraded in surface water, groundwater and soil. A recent study conducted for the Governors' Ethanol Coalition, "The Fate and Transport of Ethanol-Blended Gasoline in the Environment," concluded that ethanol poses no threat to surface water and ground water. According to the report, ethanol is a naturally occurring substance produced during the fermentation of organic matter and is expected to rapidly biodegrade in essentially all environments.
Doesn't ethanol make gasoline spills worse by promoting the spread of benzene in the soil?
Ethanol is the most harmless and biodegradable component of gasoline. When gasoline contaminates soil or water, ethanol is the first component to quickly, safely, and naturally biodegrade. A study commissioned by the MTBE industry suggested that in the event of a gasoline spill or leak, since ethanol breaks down first, benzene would persist in the environment longer. But this ignores the fact that ethanol-blended fuels contain less benzene, and the real threat posed to the environment is from the presence of benzene in gasoline, not ethanol.
Doesn't ethanol-blended gasoline increase the emission of acetaldehyde?
The California Environmental Policy Committee, in a December 1999 review of the air quality impacts of ethanol, concluded that while the use of ethanol does result in slightly increased levels of acetaldehyde and peroxyacetyl nitrate (PAN), "these compounds are more than offset by reductions in formaldehyde," a toxic air contaminant many times more harmful than acetaldehyde. Furthermore, the Committee concluded other gasoline components are primarily responsible for these emissions. "Other components of gasoline, such as aromatic compounds and olefins, are primarily responsible for the formation of formaldehyde, acetaldehyde, and PAN due to both their greater abundance in gasoline and their shorter atmospheric lifetimes."
Doesn't ethanol-blended gasoline increase smog?
Some ethanol opponents seize upon the fact that when ethanol is blended with gasoline, it slightly raises the volatility of the fuel. Increased volatility can lead to increased evaporation of smog-forming emissions. But as is often the case, this is only half the story.
Blending ethanol in gasoline dramatically reduces carbon monoxide tailpipe emissions. According to the National Research Council, carbon monoxide emissions are responsible for as much as 20% of smog formation. Additionally, ethanol-blended fuels reduce tailpipe emissions of volatile organic compounds, which readily form ozone in the atmosphere. Thus, the use of ethanol plays an important role in smog reduction.
Importantly, in reformulated gasoline areas where smog is of most concern, gasoline blended with ethanol must meet the same evaporative emission standard as gasoline without ethanol. These ethanol blends have the added benefit of providing reduced tailpipe carbon monoxide emissions and, therefore, further emissions reductions of smog.
Doesn't it take more energy to produce ethanol than you get from it?
No. Whether produced from corn or other biomass feedstocks, ethanol generates more energy than used during production. A 1996 study by the U.S. Department of Agriculture demonstrates the significant energy efficiency improvements that have been made in ethanol production due to higher yielding corn varieties, technological advances in ethanol production such as the use of molecular sieves and natural gas, and improved farming practices (precision and no-till farming). The study reviewed the entire fuel-cycle and concluded ethanol contains 34% more energy than is used in the production process, including the energy used to grow, harvest and process grain into ethanol. By comparison, ExxonMobil states, "gasoline based fuels retain about 85% of the energy originally contained in the crude oil."
In addition, a 1997 analysis by the U.S. Department of Energy's Argonne National Laboratory found that ethanol production from corn reduces fossil energy use by 50 to 60 percent compared with conventional gasoline. The full fuel-cycle analysis found that even further reductions in fossil energy use could be made with the production of ethanol from cellulose.
According to the U.S. Department of Energy, ethanol produced from biomass feedstocks generates 6.8 Btu for every Btu of fossil energy consumed. The production of reformulated gasoline without ethanol generates only 0.79 Btu for every Btu of fossil energy consumed.
Doesn't ethanol pose the same health risks as MTBE?
Absolutely not. Ethanol is produced from grains and other biomass in much the same way as beverage alcohol, which has been consumed by humans since the beginning of time. MTBE, on the other hand, is a toxic additive produced from natural gas and methanol. According to a report by Cambridge Environmental, exposure to ethanol vapors coming from ethanol-blended gasoline is very unlikely to have any adverse health consequences. Because ethanol is naturally present in blood and the body rapidly eliminates ethanol, exposure to ethanol vapors is unlikely to harm health in any way.
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