Energy and Grain Crops: An Analysis of Biomass, Energy Production, and Transportation, Study notes of Chemistry

Download Energy and Grain Crops: An Analysis of Biomass, Energy Production, and Transportation and more Study notes Chemistry in PDF only on Docsity! Biomass, Bioenergy, & Biofuels Energy, Environmental Impacts, and Sustainability Kansas State University- January 4-6, 2006 Mark Schrock Biological and Agricultural Engineering Kansas State University Manhattan, Kansas 0 5000 10000 15000 20000 25000 1965 1970 1975 1980 1985 1990 1995 2000 2005 Year O il C on su m pt io n, th ou sa nd b bl s/ da y USA Europe Former Soviet Union Middle East Africa Asia Pacific Source: BP, 2002 Petroleum Consumption Trends Comparing the Energy Market to Agriculture US Vehicle Fuel Consumption, 1999 Billion Gallons Gasoline 123 Diesel Fuel 33 Source: DOE Agriculture’s Energy Potential: Energy contained in U.S. grain crops, total above-ground biomass. Grain Record Bushels (Millions1) Year of Record Grain Weight (lbs/bu) Residue Weight (lbs/bu) Above- Ground Biomass (MillionLbs) Biomass Energy2 (BillionBTU) Biomass Energy Gasoline Equiv.3 (BillionGal) Corn 11,800 2004 56 56 1,321,600 9,912,000 85.4 Grain Sorghum 1,120 1985 56 56 125,440 940,800 8.1 Wheat 2,785 1981 60 100 445,600 3,342,000 28.8 Soybeans 3,120 2004 60 50 374,400 2,808,000 24.2 Total 146.5 Notes: 1. USDA-NASS, 2. Assumed 7,500 BTU/lb, 3. Assumed 116,000 BTU/gal US Gasoline Consumption ~123 Billion Gallon Conclusion: Energy is a MUCH larger market than food. Relative Food and Energy Prices 0 10 20 30 40 50 60 1950 1960 1970 1980 1990 2000 Year Pr ic e, $ /u ni t Winter Wheat Crude Oil Prices in Current Dollars Wheat, $/Bushel Crude Oil, $/Barrel 1973: 1 Bushel bought 1 Barrel 2005: ~17 Bushels bought 1 Barrel 2005: 1 Bushel of Wheat bought 1 GALLON of Diesel fuel. Hydrogen Issues: • Supply/Cost • Storage • Range • Safety MDS Prediction: This WON’T be cheap. Moving Transportation Beyond Petroleum Conserve Change Transportation Mode Mix Transition to Renewables 1949 1964 1973 Current 2005: Class 8 Trucks Burn ~ ½ of US Diesel fuel Container Freight Multi-Mode *Ship *Train eTruck Waterborne Class 1 Railroad ‘ | Pipeline oO 1 2 3 Energy Intensity (BTU/ton-m) Thousands Comparing Transportation Modes Current Fuel: • Gasoline (SI) • Diesel (CI) Future Fuel: • Liquids • Fuel Cell? • Battery? 2 Degrees of Freedom Moderate Weight Sensitivity Comparing Transportation Modes Current Fuel: • AvGas (SI) • Jet A, JP-4 (Turbines) Future Fuel: •Liquids • (Incl. Biodiesel) •Alternatives (Fuel Cell, etc) are tenuous! Three Degrees of Freedom Very High Weight Sensitivity Very Demanding Fuel Requirements Efficiency of Photosynthesis 11% is Absolute Top Theoretical Efficiency Losses are Estimated at: Evolutionary Survival 20-25% Respiration (Structure, etc) 20-100% So New Practical Peak = ~5% Sunlight to Sugar Source: Smil Efficiency of Photosynthesis Crassulacean Acid Metabolism Separates (in time) energy absorption And carbon fixation Most Common Limit to Photosynthesis is WATER Lowest Transpiration Loss: 400-500 moles H2O per mole CO2 Fixed Source: Smil C3 C4 Saturation of Radiation, W/m2 300 None Best Temperature, oC 15-25 30-45 Moles H2O per mole CO2 Fixed: 900-1200 400-500 Maximum Daily Growth: g/m2 34-39 50-54 Daily Max, Average for Season: g/m2 13 22 Comparing Photosynthetic Pathways Source: Smil Solar Conversion Efficiency C3 Crops 0.1-0.7% Best C4 (Sugar Cane) 1.5-2.5% Global Mean ~0.3% Kansas Farmland (0.5%) $500-4000/ac PV Array (12%) $2,000,000/ac Source: Smil BioEnergy Issues: Does it Really Produce Energy? Energy Profit Ratio = Energy Out / Energy In Energy Profit Ratio US Domestic Petroleum 0 5 10 15 20 25 30 1915 1925 1935 1945 1955 1965 1975 1985 Year En er gy P ro fit R at io Source: Gever, et al. (1986) Production vs Mining… Seed Fertilizer Energy Custom Work Chemicals Misc Energy Inputs for Corn Production: Source: Shapouri, Duffield, & Wang, 2004 27,000 btu/bu 17,000 btu/bu Total Inputs = 49,753 btu / bu Energy Balance for Ethanol Production: W/Credits No Credits W/Credits Adjusted BTU/Gal. BTU/Gal. BTU/Gal. Corn Production 18713 12350 18713 Corn Transport 2120 1399 2120 Ethanol Conversion 49733 30586 49733 Ethanol Distribution 1487 1467 1487 Total Energy Used 72052 45802 72052 Net Energy 4278 30528 30528 Ethanol Energy Value 76330 76330 102580 Energy Out/In 1.06 1.67 1.42 Source: Shapouri, Duffield, & Wang, 2004 Opportunities for Improving Ethanol’s Energy Balance: Corn Fertilization, especially Nitrogen Ethanol Processing (Cogen) Other Biodiesel EPRs: Energy Out/Energy In Corn Oil, Illinois 3.95 Cotton Seed Oil, Texas 1.76 Crambe, Kentucky 3.11 Peanut, Georgia 2.26 Spring Rape, Canada 4.18 Safflower, California 3.39 Soybeans, Illinois 4.56 Sunflowers, North Dakota 3.5 All Crops Dryland Production Source: Goering & Daugherty, 1982 Basic Esterification: Vegetable oils Recycled Greases | Methanol + KOH t Methanol Crude Glycerin recovery , all Glycerin refining Glycerin t Dilute Acid 4 Sulfur + Esterification methanol Crude biodiesel Refining Biodiesel Low Pressures Low Temperatures  “oo 7 20 40 60 Temperature (deg C) FIG. 1, Viscosity of soybean oil, soybean oil esters and diesel fuel in centistokes as a function of temperature, C. &}——9 Diesel, ®— ethyl, -4—A methyl, x— soybean oil. Desirable Traits for Energy Crops Legume (or low protein product) Perennial (low energy inputs) Low Processing Energy Good Yields on Dryland Two Paths: Adapt food crops to energy production Domesticate new energy crops Temperate Legume Annual Cultivated for 3000 yrs Seed Yield 3.1 Mg/ha Oil Content 17-26% Oil Yield 650 kg/ha Ref: CIGR V. Soybean Glycine max Seed Yield 2 Mg/ha (30 bu/ac) Oil Content 18% Oil Yield 360 kg/ha (46 gal/ac) Sunflower Helianthus annus Temperate Annual Seed Yield 3.7 Mg/ha Oil Content 35-40% Oil Yield 1400 kg/ha Ref: CIGR V. Seed Yield 1.7(dry)-3.4 (irr) Mg/ha Oil Content 40% Oil Yield 700-1400 kg/ha (90-180 gal/ac) Ref: KSU Hybrid Trials Temperate Annual Pacific NW, Canada, China Seed Yield 3 Mg/ha Oil Content 33-40% Oil Yield 1100 kg/ha (140 gal/ac) Ref: CIGR V. Rape Canola (low erucic Rape) Brassica napus Idaho Biofuels Program Temperate Annual Pacific NW Seed Yield 4.5 Mg/ha Oil Content 25-37% Oil Yield 1300 kg/ha Ref: CIGR V. Safflower Carthamus tinctorius Crambe Crambe abyssinica Temperate Annual Seed Yield 5 Mg/ha Oil Content 36% Oil Yield 1800 kg/ha (225 gal/ac) Ref: CIGR V. German-French Tests (dry): “dt” = 100 kg Class IV Land: Marginally Arable Sandy Topsoil (High Erosion & Low Water Capacity) Winter Wheat (intended crop) Temporary Windbreak (reduces wind erosion) Perennial Windbreak Water Table < 5 m. Deep Why Force Marginal Land Into Annual Agriculture? Kansas Cash Rental Rates: Rangeland $31.12/ha Non-Irrigated Cropland $88.92/ha Kansas Land Use: Rangeland 6.7 x 106 ha Cropland 12.7 x 106 ha Total Land Area 21.2 x 106 ha Is $15/ac the Best We Can Do? Tropical Perennial Invasive Weed in Florida, Texas Seed Yield 14 Mg/ha Oil Content 55% Oil Yield 7700 kg/ha (970 gal/ac) Ref: CIGR V. Chinese Tallow Tree Sapium sebiferum Jatropha curcas Tropical Shrub ~ 3 m tall E. Africa Seed Yield 8 Mg/ha Oil Content 50% Oil Yield 4000 kg/ha (500 gal/ac) Ref: CIGR V. African Oil Palm Elaeis Guineensis West Tropical Africa Oil Yield 2200 kg/ha (280 gal/ac) Ref: CIGR V.