Biomass Combustion Another "green-powered" source of electricity comes from burning biomass, such as timber byproducts, energy crops, like switchgrass, and combustible waste products of food and fiber processing like walnut shells and peanut hulls. Other biomass material that has been used as a fuel source include:
Presently, the economics of growing biomass and harvesting it solely for generating electricity cannot compete with coal and other conventional fuels. But, where burnable biomass exists as a waste product of another process, it makes sense to convert it to energy rather than land filling it. If there is not sufficient biomass to warrant full-scale power generation, or if it's produced seasonally rather than steadily it can be co-fired in a mixture with coal. One example comes from Georgia Power which has worked with peanut processors to co-fire spent peanut shells. One peanut processor, Stephens Industries, must dispose of approximately 1000 tons a month of peanut hulls that cannot be used for such things as mulch, cat litter and fire logs. Georgia Power worked with the firm to co-fire the hulls in a mixture of coal which showed no adverse affect at the Plant Mitchell Generating Station. It is estimated that every truckload of peanut hulls saves Georgia Power approximately $400 in fuel costs. In southwest Louisiana, there are using rice hulls to power a rice processing plant, selling surplus electricity to the local utility. Agra Electric Power Partners has been converting rice hulls into electricity for several years. Most of the power is used to operate the rice mill from which the hulls come. Any extra power is sold to Entergy, the regional electrical utility. |
