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Air Quality | Water | Energy | How to be Green
Ethanol is a Renewable Resource with Positive Environmental Benefits
The increased use of ethanol is helping to reduce greenhouse gas emissions resulting from America’s cars. The production and use of 6.5 billion gallons of ethanol in 2007 resulted in the reduction of carbon dioxide and greenhouse gas emissions by 10 million tons, the equivalent of removing more than 1.5 million cars from the roads.10 Corn ethanol reduces tailpipe carbon monoxide (CO) emissions by an average of 20%; reduces volatile organic compounds (VOCs) which readily form ozone in the atmosphere; and reduces secondary particulate matter formation by 50%.11
Ethanol is good for the environment and 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 10% ethanol blends reduces greenhouse gas emissions by 18-29% compared with conventional gasoline, according to Argonne National Laboratory.
Cleaner Air - According to the EPA, gasoline is the largest source of manmade carcinogens. Ethanol is one of the best tools we have to combat air pollution from vehicles. As mentioned above, ethanol is 35%t oxygen and as a result, combusts very cleanly. This results in less smog and other forms of pollution in cities (RFA 2007). Ethanol is naturally cleaner than gasoline. It emits less hydrocarbons, nitrogen oxides, carbon monoxide and hydrogen. Ethanol reduces carbon monoxide emissions by an average of 20% —and less carbon monoxide helps reduce ozone formation and helps reduce levels of greenhouse gases. Ethanol reduces overall toxic pollution by displacing or diluting harmful compounds found in gasoline such as benzene and other aromatics.
Cleaner Water - Unlike other forms of gasoline oxygenates, ethanol is a non-toxic, biodegradable fuel that is water soluble. As a result, ethanol is surprisingly benign, posing little threat to human or environmental well-being.
Positive Energy Balance - Ethanol has a positive energy balance. On average, corn ethanol delivers 67 percent more energy output than it takes to produce (1.67:1, USDA). This means ethanol yields 67 percent more fossil energy than is used to grow and harvest the grain and process it into ethanol; or for every 100 BTUs of energy used to make ethanol, 167 BTUs of ethanol is produced.
Gasoline, on the other hand, has a negative energy balance. It uses 23% more fossil energy to make one unit of petroleum gasoline (1:1.23). In other words, gasoline requires more than one Btu of energy to deliver one Btu to your car.
The net energy balance of ethanol production continues to improve because ethanol production is becoming more efficient. A March 2008 study by the U.S. Department of Energy’s Argonne National Laboratory found significant gains just since 2001 and ethanol energy yield continues to increase as farming practices improve, corn yields increase, and ethanol production facilities incorporate the latest in technology.
Cilion's California plants have an even greater energy balance of 2.6:1 that was verified by an energy and greenhouse gas fuel cycle analysis by U.C. Berkeley's Renewable and Appropriate Energy Laboratory-Energy and Resource Group, under the direction of University of California, Berkley Professor of Energy Dan Kamen, Ph.D. The study entitled "Fuel Cycle Assessment of Ethanol Produced at Cilion's Keyes Ethanol Plant." examined the life cycle net energy balance, as well as the life cycle of greenhouse gases and criteria pollutants (with the fuel cycle defined as energy required to plant, grow, harvest and transport the corn - as well as the energy required to manufacture and distribute the ethanol).
Using established, scientifically peer-reviewed methodologies and up-to-date corn production data from fuel-stock procurement regions, U.C. Berkeley studied our life cycle net energy balanace and the life cycle of greenhouse gases and criteria pollutants determining that our California facilities have a positive energy balance of 2.6:1 and offer significantly reduced life cycle global warming emissions which also translates into an additional 29% reduction in global warming intensity (GWI) from average corn ethanol produced in a natural gas fired dry mill, and a 46% reduction in GWI versus California Reformulated Gasoline (CARFG) without oxygenate.
Our higher 2.6:1 positive energy output can be attributed to several things, including: 1) the use of steam letdown turbine cogeneration which use the steam produced to cook the corn to produce most, if not all, of the electrical energy for the facility; and 2) because we employ a destination based model in California, meaning that we are located where there is a demand for both the ethanol and our co-product, we are not drying the distillers grain thus using 33% less natural gas than the inudstry standard. What this means is that for every 1 unit of energy it takes to plant, grow, harvest, transport and convert the corn into ethanol, Cilion's California plants are receiving 2.6 units of energy from the ethanol.
The net energy balance of ethanol production continues to improve because ethanol production is becoming more efficient. For example, one bushel of corn now yields almost 3 gallons of ethanol - up from 2.5 gallons just a few years ago.
Corn ethanol is a stepping stone to cellulosic ethanol. Research is underway to develop technology to use corn more efficiently as well as using other cellulosic biomass to produce energy. With cellulosic conversion technology, ethanol producers will be able to make ethanol from a variety of sources including trees, grass, and other plants. However, research and development infrastructure is needed to develop this technology and significant capital investment is required. Corn ethanol serves the purpose of both providing the resources for research and development, and the financial investment needed to establish the industry.
Less Greenhouse Gas - According to Argonne National Laboratory (a non-profit research laboratory operated by the University of Chicago for the Department of Energy, http://www.anl.gov/), the use of 10 percent ethanol blends reduce greenhouse gas emissions by 18-29 percent compared with conventional gasoline. Using ethanol reduces greenhouse gas emissions due to the carbon cycle of plant based fuels.
The DOE's Argonne National Laboratory has also concluded that the production and use of 6.5 billion gallons of ethanol in 2007 resulted in the reduction of C02 and greenhouse gas emissions by 10 million tons, the equivalent of removing more than 1.5 million cars from the American roads (GREET 1.7 Model). Corn ethanol reduces tailpipe carbon monoxide (CO) emissions by an average of 20%, as well as reduces volatile organic compounds (VOCs) which readily form ozone in the atmosphere. As a result of diluting the aromatic content in gasoline, ethanol also reduces secondary particulate matter formation by 50%.
Futher, as previously stated, Cilion's California ethanol facilities will offer significantly reduced life cycle global warming emissions trhough cogeneration of electricity and avoidance of drying distillers grains and thus, offers an additional 29% reduction in global warming intensity (GWI) from average corn ethanol produced in a natural gas fired dry mill, and a 46% reduction in GWI versus California Reformulated Gasoline (CARFG) without oxygenate. For the same reasons, study also concluded Cilion ethanol offers lower total emissions of all criteria pollutants tracked in GREET versus the same Midwest ethanol.
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