Bioenergy
Biomass was the leading source of renewable energy in the United States in 2003, for the fourth year in a row, providing 8.5(e11) kWh of the 2.05(e13) kWh of energy produced. Biomass was the source of nearly half the renewable energy produced and accounted for 4 percent of the total energy produced in the United States (DOE 2005). Wood, and in particular residues from paper mills, are the most common resource used for generating electricity and industrial process heat and steam.
Currently, consumption of biomass generated energy is dominated by industrial use. The pulp and paper industries, solely using black liquor, consumed 3.22(e11) kWh of biomass generated energy (DOE 2005). Schools, prisons, and hospitals have recently started utilizing wood to produce energy at the local level. The residential sector consumed 9.73(e8) kWh of energy in 2004 (DOE 2005) and many other institutions are utilizing bioenergy on a variety of scales from 996 kWh up to 15001 kWh per hour (Zerbe 2006).
Companies who have ready access to biomass resources, at relatively low costs, often choose to mix traditional fossil fuels with biomass to enhance their competitiveness in the marketplace. With new emissions standards and carbon credits on the horizon, as well as consumer demand for green energy, more companies are looking to use biomass powered systems. For a more complete understanding of how energy and heat is produced from biomass, explore this encyclopedias section on production methods.
Energy production from biomass is a promising option with the potential largest impact occuring in developing countries, where the current level of energy services are low or non-existant. Biomass currently accounts for about one-third of all energy consumed in developing countries as a whole, and nearly 90 percent in some of the least developed countries. Over 2 billion persons depend on biomass energy for cooking and heating (Kartha & Larson 2000).
The following chart shows the comparative heating values of various commercial fuels used today for energy production (Payne 1980, UNEC 1978).
Use of liquid transportation fuels such as ethanol, methanol, and biodiesel, derived from biomass resources, are increasing rapidly as oil prices exceed $70 per barrel. Currently most of the ethanol and biodiesel generated in the United States comes from agricultural crops, but technological advances may make wood feedstocks for transportation fuels more appealing. In 2003, 2.81 billion gallons of ethanol were produced from corn alone (RFA 2005).
Ethanol and biodiesel can be used directly or blended with gasoline and diesel. Toxic air emmisions, greenhouse gas emissions, and dependence on unstable foreign oil all can be reduced by using biobased fuels and at the same time support rural community development (Wyman 1996). While current production of biofuels can not meet the daily demand in the United States, research is ongoing to improve production processes.
Fuels from Biomass
Encyclopedia ID: p1187
