Biomass energy is a renewable, homegrown energy source that includes trees, farm crops, manure, plants, and landfill gas. How biomass works is very simple. The waste wood, tree branches and other scraps are gathered together from factories and from farms to a biomass power plant. Here the biomass is dumped into huge hoppers. This is then fed into a furnace where it is burned. The heat is used to boil water in the boiler, and the energy in the steam is used to turn turbines and generators.
Biomass can also be tapped right at the landfill. When garbage decomposes, it gives off methane gas (natural gas is made up of methane). Pipelines are put into the landfills and the methane gas can be collected and then used in power plants to make electricity. This type of biomass is called landfill gas.
Biomass is a renewable energy source because we can always grow more trees and crops, and waste will always exist. Biomass fuels provided about 5% of the energy used in the United States in 2012. Of this, about 45% was from wood and wood- derived biomass, 44% from biofuels (mainly ethanol), and about 11% from municipal waste. Researchers are trying to develop ways to burn more biomass and less fossil fuels. Using biomass for energy may cut back on waste and greenhouse gas emissions.