ENERGY FROM BIOMASS

Biomass

• Biomass energy is energy produced from burning wood or plant residue, or from organic wastes (manure, dung).

• Algae is most energy efficient form for biofuel.

Main Goals

• Production of– Heat

– Electricity

– Biofuels• Distillation of

biomass

Geographical Locations

Heat

• For over a century, wood was the primary source of energy in the U.S.

• Is still main source of energy in South America and Southeast Asia

• Provides 20% to 80% of energy demand in most countries

Biofuels

• Can be used to produce electricity or fuel for transportation

• Examples – ethanol, biodiesel

• Sources (ethanol) – sugar cane, corn, rice, sorghum, sugar beets

• Ethanol is produced by fermenting and distilling sugar or starches

Economic and Food Supply Concerns

• There is not enough land area to grow crops for food and biodiesel.– The bulk of corn grown in the US is to provide animal feed and the

food ingredient, high fructose corn syrup.

• If farmers began to sell their corn to ethanol producers, what would happen to the demand, and therefore, the price of corn on the national market?

• How will this affect economics for the – Farmer?– Consumer?

• How and what types of products will be most affected?

Ethanol

• Most widely used biofuel • Added to gasoline to

increase octane and improve emissions quality (E10 or E85 blends)

• Clean Air Act Amendments (1990) mandated sale of oxygenated fuels in areas with unhealthy CO levels

• Can be used in all gasoline engines

Biodiesel• Produced from left over vegetable oils,

animals fats and recycled greases

• Used in diesel engines (B20 blend)• Used in some federal, state and transit

fleets• Neat blends are used in tourist boats

and at marinas and launches

• The Energy Policy Act (EP Act) of 1992 was amended in 1998 to allow regulated fleets to use 450 gallons of biodiesel/vehicle/year in order to earn EP Act credit in order to help extend diesel fuel supply.

Waste-to-Energy

• Combustion of garbage

• Land fill gas– Methane produced from

decomposing garbage can be captured and used as a fuel source

Advantages

• Renewable energy source• Available worldwide• Relatively inexpensive• Carbon neutral emissions because carbon is sequestered

by plant, then released by burning• Reduction in carbon dioxide emissions (GHG)• Reduction in CO emissions (primary pollutant)• Great use of waste products• Can help boost the economy• Can reduce dependence of foreign oil

Disadvantages

• Can NOT provide enough energy to supply large demands• Could increase to deforestation and loss of biodiversity in

less developed countries• Not currently developed enough to rely on as a steady

energy source• Large land requirements• Soil degradation• Emissions do contain GHGs (NOx)• Increased NOx emissions• Net loss of energy