Liquid Biofuel Technologies and Technology Issues

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1 Liquid Biofuel Technologies and Technology Issues Eric D. Larson Princeton Environmental Institute Princeton University, Princeton, NJ USA UNCTAD Biofuels Workshop 30 November 2006 Geneva, Switzerland

2 U.S. Fuel Ethanol Production Million Gallons Fuel Ethano

3 U.S Ethanol and Biodiesel Capacity Ethanol (corn) 107 existing plants 5.1 billion gal/yr capacity 1 to 1000 million gal/yr individual plant capacities 49 plants being built 3.9 billion gal/yr capacity Approximately 15% of U.S. corn crop in 2005 was used to make ethanol, and the ethanol displaced less than 2% of transportation oil use. Biodiesel (soy) 87 existing plants 0.6 billion gal/yr capacity 0.5 to 37 million gal/yr individual plant capacities 65 plants being built 1.4 billion gal/yr capacity

4 Biofuel Technology Issues Objectives for a biofuel program Transportation fuel security vs. broader energy replacement? Land reclamation? Rural employment and development? Export revenue? Global warming mitigation? Issues for different biofuels Land requirements. Conversion technology scale and sophistication. Economics (feedstock, conversion, delivery, and use). Environmental impacts (lifecycle) Compatibility with existing fuel delivery/use infrastructures Competing uses for biomass (for energy or for other).

5 Biofuels First Generation (from sugars, grains, or seeds) Biodiesel (fatty acid methyl ester; fatty acid ethyl ester) rapeseed (RME), soybeans (SME), sunflowers, jatropha, coconut, palm, recycled cooking oil Pure plant oils (straight vegetable oil). Bioethanol From grains or seeds: corn, wheat, potato From sugar crops: sugar beets, sugarcane Second Generation (from lignocellulose: crop residues, grasses, woody crops) Ethanol via enzymatic hydrolysis Thermochemical fuels Fischer-Tropsch liquids (FTL) Methanol, MTBE, gasoline Dimethyl ether (DME) via gasification Mixed alcohols Hydrogen Hydrothermal upgrading oils (HTU) Pyrolysis oils

6 Biofuel Production Pathways LPG Petrol Diesel CNG, LNG Mixed Green FTL DME MeOH Ethanol Biodiesel OH Diesel Green Diesel Blending Synthesis Refining Esterification Refining Refining Gasification Pyrolysis Fermentation Extraction Hydro- Thermal Upgrading Hydrolysis Anaerobic Digestion (Biogas) Crude oil Natural gas Coal Lignocellulosic biomass Sugar and starch crops Oil crops Wet biomass FOSSIL FUELS BIOMASS Second Generation First Generation

7 Biofuel Ethanol Mixed alcohols Methanol Fischer Tropsch Biodiesel Green diesel Dimethyl ether Biocrude Conventional Fuel Gasoline Diesel LPG Paraffin Kerosene Crude oil

8 Biofuel Cooking Fuel Ethanol Alcohol Gel Methanol Mixed OH LPG DME cleanest options DME Paraffin FTL Kerosene 4 to 5 EJ/year needed globally if all 3 billion people still cooking with solid fuels were using clean fuels instead [35 kg/cap/yr of LPG equivalent]. U.S. transportation oil use in 2005 was 29 EJ. Global commercial energy use in 2005 was ~ 450 EJ.

9 Transportation Services Per Hectare vehicle-km per hectare per year RME (Netherlands) EtOH from maize (USA) EtOH from wheat (Netherlands) EtOH from sugar beets (Netherlands) EtOH from sugarcane (Brazil) EtOH from wood (present technology) EtOH from wood (advanced technology) MeOH from wood (by gasification) H2 from wood (by gasification)

10 Relative GHG mitigation with biofuels vs. bio-electricity depends on: The cultivation process to make the biomass. The biofuel being produced. The conversion technologies being used. The fossil fuel systems being displaced. Higher biomass yields (10 t/ha/yr); Diesel-cycle engine. Lower biomass yields; Ottocycle engine. 2 nd generation biofuels CONCAWE et al

11 1 ost vs. Scale, 2 nd Generation Biofuels Unit Production Cost Total Capital Biomass economic optimum 0 Conversion Facility Size

12 First Generation Biofuels Use of sugar or starch crops creates limitations: Competition for food uses. Plants optimized for food, not energy. Only part of the plant is converted to biofuel. Co-product sales often important for acceptable economics. Only modest energy and GHG benefits, except with sugarcane ethanol (due to greater utilization of the above-ground biomass). Can blend with existing petroleum-derived motor fuels minimal infrastructure change. Limited large-scale experience outside Brazil and USA. Relatively high costs (except sugarcane ethanol in Brazil) due to high feedstock cost. Cost penalties less severe at smaller scales. 1

13 Second Generation Biofuels Made from lignocellulosic materials These are generally not edible. Plants can be bred for energy characteristics. Larger fraction of the plant is converted to fuel. Biorefinery maximizes plant utilization. Substantial energy/environment benefits. Can blend with petroleum fuels in most cases. Greater capital-intensity than 1 st generation biofuels, but lower feedstock costs higher costscale sensitivity than with 1 st generation means larger scale of conversion facilities needed. Thermochemical and biological secondgeneration biofuels are different. 1

14 1 2 nd Generation: Thermochemical FT, DME, methanol, mixed-alcohols Allows complete utilization of the biomass. High degree of feedstock flexibility. Conversion technologies available today for FT, DME, MeOH no R&D breakthroughs. Commercial-scale implementation is lacking today, but large overlap (and synergies) with commercially established fossil fuel conversion technologies. One commercial facility in planning (Germany).

15 2 nd Generation: Biological Cellulosic ethanol Limited fraction of the biomass can be converted with known enzymatic technology today. Lignin not convertible in any case, but can use for heat or co-product. Limited feedstock flexibility micro-organisms must be tailored to the feestock. R&D breakthroughs needed to improve conversion and reduce costs. Projected costs are somewhat less scale sensitive than for thermochemical fuels. One commercial facility in planning (Idaho, USA). 1

From Biomass. NREL Leads the Way. to Biofuels

From Biomass. NREL Leads the Way. to Biofuels From Biomass NREL Leads the Way to Biofuels The Wide World of Biofuels Fuel Source Benefits Maturity Grain/Sugar Ethanol Biodiesel Corn, sorghum, and sugarcane Vegetable oils, fats, and greases Produces