Renewable Energy from Biomass

Direct combustion of gas produced from biomass, or biogas, to generate Electricity and/or heat – e.g. wood stoves or larger commercial operations.

Biomass makes up about 7,000 Megawatts of renewable electricity. Biomass fuels stem from industrial processing, such as forestry and wood products, agriculture and wood products, and construction and transportation. Biomass can replace coal in power plants because it produces less sulfur dioxide than coal.

Mill operations seem to be the main source of biomass energy in the U.S. Europe, on the other hand, draws its main source of bioenergy from urban wood waste. Third world countries make timber their main source of bioenergy.

According from statistics from the International Energy Agency, 11% of the world derives its energy from biomass. Developing countries use about 35%, while the poorest ones use roughly 90%.

One way to convert biomass into usable energy is through gasification—converting biomass to gas and burning it in a gas turbine.

Biomass Energy Types

Biomass energy is produced from non-fossilized materials derived from plants. Wood and wood waste are the largest sources of biomass energy followed by energy from municipal solid waste (MSW) and alcohol fuels. In 2004, biomass accounted for 47% of renewable energy consumption, with about 50% of this used for heating, 40% for electrical power production, and the rest as transportation fuel.

Wood

Wood biomass includes wood chips from forestry operations, residues from lumber, pulp/paper, and furniture mills, and fuel wood for space heating. The largest single source of wood energy is “black liquor,” a residue of pulp, paper, and paperboard production. It supplies over 50% of these industries’ energy requirements. Lumber mills and furniture manufacturers use chips, sawdust and bark for nearly 60% of their energy requirements. A small but growing amount of wood is co-fired with coal in utility power plants. Cordwood, wood chips, and pellets made from sawdust are used for space and water heating in buildings, including in over two million households as primary or supplemental heating fuels.

Municipal Solid Waste and Biogas

Another source of biomass is our garbage, also called municipal solid waste (MSW). Trash that comes from plant or animal products is biomass. Food scraps, lawn clippings, and leaves are all examples of biomass trash. Materials that are made out of glass, plastic, and metals are not biomass because they are made out of non-renewable materials. MSW can be a source of energy by either burning MSW in waste-to-energy plants, or by capturing biogas. In waste-to-energy plants, trash is burned to produce steam that can be used either to heat buildings or to generate electricity. In landfills, biomass rots and releases methane gas, also called biogas or landfill gas. Some landfills have a system that collects the methane gas so that it can be used as a fuel source. Some dairy farmers collect biogas from tanks called “digesters” where they put all of the muck and manure from their barns. Read about a field trip to a real waste-to-energy plant or learn about the history of MSW.

Biofuls

“Biofuels” are transportation fuels like ethanol and biodiesel that are made from biomass materials. These fuels are usually blended with the petroleum fuels – gasoline and diesel fuel, but they can also be used on their own. Using ethanol or biodiesel means we don’t burn quite as much fossil fuel. Ethanol and biodiesel are usually more expensive than the fossil fuels that they replace but they are also cleaner burning fuels, producing fewer air pollutants. Ethanol is an alcohol fuel made from the sugars found in grains, such as corn, sorghum, and wheat, as well as potato skins, rice, sugar cane, sugar beets, and yard clippings. Scientists are working on cheaper ways to make ethanol by using all parts of plants and trees. Farmers are experimenting with “woody crops”, mostly small poplar trees and switchgrass, to see if they can grow them cheaply and abundantly. Most of the ethanol used in the United States today is distilled from corn. About 99 percent of the ethanol produced in the United States is used to make “E10″ or “gasohol” a mixture of 10 percent ethanol and 90 percent gasoline. Any gasoline powered engine can use E10 but only specially made vehicles can run on E85, a fuel that is 85 percent ethanol and 15 percent gasoline.

Biodiesel is a fuel made with vegetable oils, fats, or greases – such as recycled restaurant grease. Biodiesel fuels can be used in diesel engines without changing them. It is the fastest growing alternative fuel in the United States. Biodiesel, a renewable fuel, is safe, biodegradable, and reduces the emissions of most air pollutants.

Why is there demand to use Biomass

Biomass can pollute the air when it is burned, though not as much as fossil fuels. Burning biomass fuels does not produce pollutants like sulfur, that can cause acid rain. When burned, biomass does release carbon dioxide, a greenhouse gas. But when biomass crops are grown, a nearly equivalent amount of carbon dioxide is captured through photosynthesis. Each of the different forms and uses of biomass impact the environment in a different way.

Types of renewable energy

Environment

• Additional planting and management of woodland
• Reduction in carbon dioxide
• Reduction in global warming

Political
All members of the EU are committed to carbon emission reduction, and Biomass forms an important part of this strategy.

The advantages will be felt across the rural economy by adding forestry and creating employment.

Commercial

• With the increase in Landfill Tax and the introduction of the latest Climate Control Levy, biomass will become even more competitive with fossil fuels.
• Biomass is a chosen growth sectors in the U.K.
• Oportunities for district heating and Combined Heat and Power (CHP) projects.
• Increased awareness of opportunities at grass roots levels and beyond.