Biomass—Wood and wood waste
People have used wood for cooking, for heat, and for light for thousands of years. Wood was the main source of energy for the world until the mid-1800s. Wood continues to be an important fuel in many countries, especially for cooking and heating in developing countries.
Source: National Renewable Energy Laboratory, U.S. Department of Energy (public domain)
In 2015, about 2% of total U.S. annual energy consumption was from wood and wood waste (bark, sawdust, wood chips, wood scrap, and paper mill residues).
Using wood and wood waste
Industry, electric power producers, and commercial businesses use most of the wood and wood waste fuel consumed in the United States. The wood and paper products industry uses wood waste to produce steam and electricity, which saves money because it reduces the amount of other fuels and electricity that must be purchased. Some coal-burning power plants burn wood chips to reduce sulfur dioxide emissions.
About 20% of total U.S. wood energy consumption in 2015 was by the residential sector, and wood accounted for about 3% of total residential energy consumption.
Wood is used in homes throughout the United States for heating as cord wood in fireplaces and wood-burning appliances and as pellets in pellet stoves. In 2012, about 2.5 million U.S. households used wood as the main heating fuel. An additional 9 million households used wood as a secondary heating fuel.