Biofuels CENV 110

Topics The Technology Current status around the world – Supply and trends in production Impact Benefits Costs – Carbon balance – Net energy – Impact on food price

The basic idea Organic matter can be converted to fuel This is where fossil fuels came from The old method is to collect firewood and either burn it directly or convert to charcoal The new technology is to grow crops – convert the crops to fuel – Reduce dependence on foreign oil – Potential for carbon neutral production – Boost farm incomes

Technology Bioethanol: made by fermenting the sugars and starches in plant matter: also some work on converting cellulose Biodiesel: made from vegetable oils and animal fats

Fermentation

Corn ethanol

Biodiesel

Biofuel feedstock Corn Soybeans Sugar cane Wheat Palm oil Agricultural residues (leftover material from crops, such as the stalks, leaves, and husks of corn plants) Forestry wastes (chips and sawdust from lumber mills, dead trees, and tree branches) Municipal solid waste (household garbage and paper products) Food processing and other industrial wastes (black liquor, a paper manufacturing by-product) Energy crops (fast-growing trees and grasses) developed just for this purpose

switchgrass

Current and trends in production

Current production

US Biofuel production

World Trend

Biofuels issues Oil price and oil dependency sustainability Food security Net energy – carbon footprint Environmental impact – Land clearance – Water use, fertilizer etc

Energy and carbon balance

Greenhouse gas net impacts Fuel PathwayReduction in GHG emissions Corn Ethanol (Natural gas dry mill)-16% Corn Ethanol (Best Case)-39% Corn Ethanol (Coal dry mill)+13% Corn Ethanol (Biomass dry mill)-39% Corn Ethanol (Biomass everywhere)-47% Soy-based biodiesel-22% Waste Grease biodiesel-80% Sugarcane Ethanol-44% Switchgrass Ethanol-128% Corn Stover Ethanol-115%

Economics of biofuels

Some other environmental costs

Potential for growth

Concerns of food security

2 nd generation or advanced biofuels Second generation biofuels are biofuels produced from sustainable feedstock. Sustainability of a feedstock is defined among others by availability of the feedstock, impact on GHG emissions and impact on biodiversity and land use. Many second generation biofuels are under development such as Cellulosic ethanol, Algae fuel, biohydrogen, biomethanol, DMF, BioDME, Fischer-Tropsch diesel, biohydrogen diesel, mixed alcohols and wood diesel.

Other potential developments Use of genetic engineering to modify crops/algae to increase yields

Summary from FAO Demand for agricultural feedstocks for liquid biofuels will be a significant factor for agricultural markets and for world agriculture over the next decade Rapidly growing demand for biofuel feedstocks has contributed to higher food prices, which pose an immediate threat to the food security of poor net food buyers (in value terms) in both urban and rural areas. In the longer term, expanded demand and increased prices for agricultural commodities may represent opportunities for agricultural and rural development The impact of biofuels on greenhouse gas emissions – one of the key motivations underlying support to the biofuel sector – differs according to feedstock, location, agricultural practice and conversion technology

More Summary from FAO Harmonized approaches for assessing greenhouse gas balances and other environmental impacts of biofuel production are needed to achieve desirable outcomes Liquid biofuels are likely to replace only a small share of global energy supplies and cannot alone eliminate our dependence on fossil fuels. Production of liquid biofuels in many countries is not currently economically viable without subsidies: sugarcane in Brazil an exception

Study Guide What is the traditional and still most common use of biofuels? Firewood for heating and cooking. Where are biofuels most commonly used in 2008? In residential use. What are the two primary forms of modern liquid biofuels? Bioethanol and biodiesel. Where is energy used in producing bioethanol from corn? Growing the crops, transporting the crops to the plant, milling, cooking and transportation to the end use. List 6 potential biofuel feedstocks Corn, soybeans, sugarcane, wheat, palm oil, agricultural residues, forestry waste, industrial waste, energy crops such as switchgrass. What is the maximum current yield in liters per hectare for biofuels About 5, this corresponds to roughly 5 tons per ha, similar to crop yields About what fraction of us gasoline consumption is US biofuel production? About 5% -- you should know it is small, but not insignificant. What country other than the US is the biggest biofuel producer? Brazil. What factors primarily affect the greenhouse gas balance of biofuels? The feedstock used, and the source of energy in the production process. How does the GHG footprint of US corn produced ethanol compare to traditional fossil fuels? Worse than natural gas, gasoline and diesel, better than coal. What biofuel technology currently in practice has the best GHG footprint? Sugar cane in Brazil. What is the role and magnitude of subsidies in US liquid biofuel production? Subsidies in the US range from $1.00 to $2.00 per gallon and are the main driver of the rapid growth in US liquid biofuels, especially corn ethanol. Why are the price of oil and of main crops tightly coupled? Oil price is a major determinant of production costs for crops, both in the cost of fertilizer and machinery operation, and there is a link because of increased use of food crops for biofuels, adding to the price of the crops. How much water does it take to produce a liter of biofuel? liters of water per liter of biofuel. What parts of the world have the greatest potential to use additional land to produce biofuels? Latin America and Sub-Saharan Africa. Why is there so much concern about the impact of biofuels on food security? Many of the poorest countries of the world now import much of their food. If more food crops are converted to biofuels, the price of food will rise, and malnutrition in poor countries will increase. What was the trend in food crop prices from the 1970s to Downward, food got cheaper.