1. Renewable Biofuel Energy Primer Acknowledgements Nebraska Energy Office University of Nebraska-Lincoln Institute of Agriculture and Natural Resources Department of Agronomy and Horticulture Development Team: Dr. Ken Cassman, Dr. Adam Liska, Leah Sandall, Patty Hain

2. Biofuel Energy System Solar radiation CO 2 O2O2 Decomposition Crop residue Soil organic matter CO 2 Ethanol Plant Transportation Cars Cattle feedlot Value-added products

3. Photosynthesis – Converting Sunlight into Plant Biomass Light CO 2 O2O2 Rain Nitrogen (N) Phosphorous (P) Potassium (K) Calcium (Ca) Iron (Fe) Essential soil nutrients Photosynthesis: process of converting light energy using water (H 2 O) and carbon dioxide (CO 2 ) into oxygen (O 2 ) and sugars (carbohydrate). Irrigation

4. Corn Grain Composition and Energy Content Sugar and starch (72%) Protein (10%) Oil (4%) Fiber (13%) Sugar and starch (carbohydrates) portion of the kernel used to make ethanol. Percent by weight Sugar and starch (67%) Protein (12%) Oil (9%) Fiber (13%) Percent of Energy Content

5. Fermentation Fermentation: microbial process of converting starch and sugars to alcohol 6000-8000 BC Primitive production of alcohol 1700’s-1800’s Commercial production of beer, bourbon/whiskey 1930’s U.S. prohibition 1970’s-present Industrial ethanol production for biofuel

6. Ethanol Production Plant Fermentation Enzymes+ Yeast Consumable Alcohol (Beer) Corn Distillation towers 190 proof Ethanol Distillers Grains and syrup separation (water + yeast/microbes) natural gas and steam *One bushel of corn 2.7 gallons of ethanol + 6.7 lbs of distillers grains

7. By-products from Grain Ethanol Production Distillers grains: used for livestock feed –can replace 20-40% of cattle rations –can be dried for long-distance shipping (energy intensive) or fed to feedlots nearby without drying Solubles: contain oil and proteins –mixed with distillers grains –processed into other value- added products

8. How much grain is needed? The Energy Security Act of 2005 and Renewable Fuels Standard (RFS) –7.5 billion gallons of ethanol by 2012 At 2.7 gal/bu corn = 2.8 billion bushels of corn needed Total U.S. corn production (2005) = 11 billion bushels Average rate of yield gain = 1.2% / year By 2012, 7.5 billion gallons of ethanol will require 23% of 11.9 billion bushel U.S. corn crop

9. Amount of Grain Needed Technological advances continue to improve ethanol production Distillers grains replace grain used for livestock feed Therefore, total grain requirements are likely to be about 15% of the U.S. corn crop in an average year

10. Is Ethanol Production Energy Efficient? One measure of energy efficiency = ratio of energy in ethanol biofuel divided by the energy used in producing, transporting, and converting corn to ethanol Ratio greater than 1.0 means more energy is produced than is consumed Based on current average values, energy ratio = 1.2

11. Energy Efficiency Will Improve Due to: –Increases in corn yield and production efficiency –Increases in ethanol conversion efficiency –Better integration of ethanol and livestock production facilities Reducing transportation distance for distillers grain Use of manure, reducing need for natural gas to run ethanol plants

12. How Does Ethanol Reduce Use of Foreign Oil? A recent economic impact study indicates that an 8 billion gallon RFS would reduce U.S. imported oil from 67% to 62% –Would reduce oil imports by 2 billion barrels For every gallon of oil used in lifecycle of ethanol production, about 8 gallons of ethanol are produced

13. Is Grain-Ethanol Production Good for the Environment? Ethanol use in gasoline decreases emissions of environmental pollutants Greenhouse gas (GHG) emissions reduced because instead of burning fossil fuels in cars (increasing GHG) the use of ethanol “recycles” CO 2 into atomosphere Implementing farming practices with increased efficiency, reduces production costs and helps protect the environment

14. Use of Oil Crops to Produce Biodiesel Fuels Soybean, canola, and other crops have seed with high percentage of oil Oil from seeds can be extracted and processed into biodiesel fuel, replacing diesel fuel made from imported oil Current biodiesel production is small but the 2005 Energy Security Act provides incentives to expand this fuel source

15. Future Developments New ethanol production from non- grain plant material –Converting cellulose in plant tissues to sugars –Plant stalks and leaves contain cellulose Plant material from corn (corn stover), switchgrass, wood residue Currently costs more to produce ethanol from biomass than from grain With technology improvements, it is estimated that ethanol production could produce up to 20% of total U.S. transportation fuel Switchgrass

16. References Farrell et al. Ethanol Can Contribute to Energy and Environmental Goals. Science 311: 506-508, 2006. Klass et al. Biomass for Renewable Energy, Fuels, and Chemicals. Academic Press 1998. Renewable Fuels Association. From Niche to Nation: Ethanol Industry Outlook, 2006. http://www.ethanolrfa.org/http://www.ethanolrfa.org/ Shapouri, H., J.A. Duffield, M. Wang. The Energy Balance of Corn Ethanol: An Update, USDA-ERS, 2002. Shapouri, H., and P. Gallagher. USDA’s 2002 Ethanol Cost-of-Production Survey. USDA-ERS, AER no. 841, 2005. Wang, M., C. Saricks, D. Santini. Effects of Fuel Ethanol Use on Fuel-Cycle Energy and Greenhouse Gas Emissions. Argonne National Laboratory, Department of Energy. ANL/ESD-38, 1999. Wyman, C.E. (Ed.). Handbook on Bioethanol: Production and Utilization. Taylor & Francis, 1996.