What are biofuels? • Fuels obtained from organic matter. – ___________________ – ___________________ Classifying Biofuels • First Generation Biofuels – Made from largely _________________ sugars and starches. – Corn, sunflower seeds, sugarcane, etc… – Criticized because directly takes away from ________________________ – Mainly processed into ethanol and biodiesel. Ethanol • Contains the same chemical compound as alcoholic beverages. • Nearly ________________ of US gasoline contains ethanol in a low-level blend. – Used to ___________________the fuel and reduce air pollution. • Also increasingly available in _______, which can be used in flex-fuel vehicles. – Can’t be used in regular vehicles because ethanol is a ____________________, meaning it can break down fuel lines in a regular car. Ethanol Production • The US, the world’s largest producer of ethanol uses corn as a feedstock. • ___________________, number 2 in ethanol production uses ____________________. Ethanol from cellulosic feedstocks. • 2nd generation biofuels. • Cellulose and other plant products cannot be ________________________ by humans, but make up the bulk of the plant. • Processes are being developed to break down cellulose into _________________ that an be fermented into ethanol. • Agricultural waste products, forestry residues, _______________________, and trees can all act as feedstocks for cellulose. • Less impact on food production. Pros and Cons of Cellulose • Pros – Abundant, can make a lot of ethanol. – Can be derived from waste products. – Can be grown on _____________ lands,(lands that are not suitable for food crops). • Cons – Removing agricultural waste from fields, like corn ______________, can increase erosion and reduce the organic content of soil. – Cellulose is difficult to break down, process is not perfected yet. Sustainability of Ethanol Production • Have to take into account all energy inputs that are required to produce ethanol. – __________ required to harvest crops and transport product to ethanol processing plants. – Ethanol processing plants require fuels and electricity to change the sugars/starches/cellulose to ethanol. – Water, _________________, __________________all have to be factored into the environmental costs. The Argument over Corn Produced Ethanol • A call to end _____________ – In 2004 the federal government added a tax credit of $0.51 cents per every gallon of gas that was mixed with ethanol. – Led to an increase in ethanol production, which increased ________________. – This increase in corn prices led to an increase in food costs for humans, and feed costs for livestock farmers. A call to continue subsidies • The tax credit is scheduled to expire December 31st of this year. • Eight farming/energy associations are petitioning the “lame duck” session of congress to extend the tax credit. • They claim without the credit ___________________ will not be as willing to add ethanol to their gasoline. • Without this demand for ___________________will shut down, and jobs will be lost. Does corn-produced ethanol lower greenhouse gas emissions? • Difficult to estimate, some studies say yes and some say no. • Remember natural ________________ absorb more CO2 than corn does. • Also have to take into account all greenhouse gas emissions coming from the production of the ethanol. • When ethanol is burned it produces ______ as well. Factors to consider • What type of fuel is used to harvest the crops, and potential future ___________________ advances that will make these products more efficient. Biodiesel • Diesel fuels have longer ____________ chain lengths. • Biodiesels are derived from a variety of sources. – Vegetable oils – Animal Fats – Used cooking oils/greases. • Created using a process called _______________________, – Removes __________________ from fat and oil molecules to create biodiesel. Make your own biodiesel • It’s the latest craze since make your own beer. • You can buy a kit, or make your own ____________________ out of an old water heater. Need a source • Many people who make biodiesel at home go to the local diner and get the used ______________________. • This isn’t exactly sustainable, not enough used cooking oil to run all the cars in the US. • Daryl Hannah loves to run her car on biodiesel made from used cooking oil. Pros and Cons of Biodiesel • Pros • Does not require ____________________ of diesel engines to be used. • Safe to transport, burns relatively cleanly. • Cons • Not as much ______________ content as regular diesel. • Some engine problems have arisen. – Recently in Minnesota, state snow plows that are run on biodiesel gelled up due to low temps, since then this problem has been dealt with, hopefully. Using Algae for Biofuel Production • Algae, a single-celled ______________________ organism is considered to be a third generation biofuel. • If you watch TV, you will occasionally see a commercial from ________________ talking about algae fuels. • Algae is being explored in a variety of ways to meet our energy needs. Algae in a Bioreactor • This is a ____________ system that allows for the growth of algae for extraction of biomass. Open Pond Systems • Some researches use open pond systems to grow algae. • Cheaper to run, more simple to maintain. • ________________ can affect the algal growth, and ____________________ can contaminate the ponds. Algae in the Ocean • Some countries don’t have room to grow algae on land, so they look to growing algae in the ocean. • The more ________________ the better, because of contamination from other undesirable algae, and tides and currents make it hard to keep the algae under control. • Better to grow close to the _______________ in controlled inland seas. Pros and Cons of Algae Biofuels • Can be converted into ___________ and ___________. • Can be grown in areas where other crops couldn’t be grown. • Sequesters _______________________, it has been suggested that industries that produce large amounts of CO2 install algae bioreactors to help reduce the greenhouse gas. • Risky, difficult to predict and prevent _______________________ of other organisms. • Still in the developmental stage, in some algae businesses have already gone bankrupt.