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Biomass energy uses organic matter such as wood or plants -- called biomass -- to create heat, generate electricity and produce fuel for cars that is dramatically cleaner than oil. Biomass energy is growing rapidly and now accounts for 45 percent of the renewable energy used in the United States. As its use expands, biomass helps America lower toxic pollutants in the air and decreases our reliance on foreign oil.

How It Works

Modern biomass energy recycles organic leftovers from forestry and agriculture, like corn stovers, rice husks, wood waste and pressed sugar cane, or uses special, fast-growing "energy crops" like willow and switchgrass, as fuel. These materials, called biomass, can be treated in different ways to produce electricity or clean-burning fuels for vehicles. Biomass can be:

• Burned like coal in power plants -- but with fewer harmful emissions -- to produce heat or electricity.



• Fermented to produce fuels, like ethanol, for cars and trucks.



• Digested by bacteria to create methane gas for powering turbines.



• Heated under special conditions, or "gasified," to break down into a clean-burning gas that can be used to make a range of products from diesel to gasoline to chemicals.

Where It's Used

Most biomass in use today is burned for heat or used to make ethanol, but other, more efficient technologies are also being developed.

• Biomass power plants across the country burn agricultural waste to generate electricity for industries and residents. A biomass plant in Burlington, Vermont, for instance, uses wood waste to generate 50 megawatts of electricity annually, or enough to power more than 120,000 area homes.



• More than 100 biomass plants in 31 states burn methane gas generated from landfills.



• Some conventional power plants substitute biomass for a fraction of the coal they normally burn, reducing their sulfur dioxide and carbon dioxide emissions. When one medium-sized power plant adds biomass to its mix, its global warming emission reductions are equivalent to taking 17,000 cars off the road.



• In the Southeast and Pacific Northwest, the lumber, pulp and paper industries supply 60 percent of the energy they need to run their factories by burning wood waste.



• American farmers and refiners produce almost 4 billion gallons of ethanol a year from corn energy crops. There are currently 84 ethanol plants in the United States, and 16 more in the works. The ethanol they produce is usually blended with gasoline. All cars and trucks can use blends of 10 percent ethanol, and there are already nearly 5 million "flexible fuel" vehicles on the road that can use up to 85 percent ethanol.

How Much It Costs

The cost of electricity from biomass energy depends on the type of biofuel used, how it's converted to electricity and the size of the plant. Power plants that burn biomass directly currently generate electricity at a cost of between 7 and 9 cents per kilowatt-hour.

Advantages

• There's plenty of biomass to go around, and we can keep growing more of it. Right now, roughly 39 million tons of crop residues go unused each year in the United States. If harnessed, this amount could produce about 7,500 megawatts of power -- enough for every home in New England.



• Unlike coal, biomass produces no harmful sulfur emissions and has significantly less nitrogen, which means it cuts down on acid rain and smog.
• Burning biomass can result in zero net carbon dioxide emissions: any carbon dioxide released by burning biomass can be taken right back out of the atmosphere by growing more biomass.



• Using biofuels in our cars results in less global warming pollution than gasoline and allows us to invest our energy dollars at home instead of in foreign oil.



• Switchgrass, a promising source of biofuel, is a native, perennial prairie grass that is better for the environment than most row crops: it reduces erosion, produces very little nitrogen runoff and increases soil carbon. It also provides good wildlife habitat.



• About half of all ethanol production plants are owned by farmer-cooperatives, meaning that biofuels not only hold great promise for the environment, but are also helping to preserve the economic vitality of rural communities.

What's Around the Corner

• Aggressive action to develop advanced biofuels between now and 2015 could allow America to produce, by 2050, the equivalent of more than three times as much oil as we currently import from the Persian Gulf. Coupled with making our vehicles more efficient, this could virtually eliminate our demand for gasoline.



• Flexible-fuel vehicle requirements are being considered at the national level that will prompt manufacturers to make all new cars and trucks capable of running on both conventional gasoline and biofuels by 2015.



• Improved high-tech "gasification" systems could bring down the cost of biomass energy to 5 cents per kilowatt-hour.



• Farmers will plant energy crops on a large scale. Researchers are testing fast-growing, cost-efficient trees such as poplar and eucalyptus, and grasses such as alfalfa and switchgrass, to be harvested as biofuels.



• More power plants will burn biomass along with coal to produce electricity in the near future. This system curbs pollution, and existing plants can recover the cost of adopting the technology within a few years.

Overview | Wind | Solar | Biomass

last revised 12/22/2005