Biomass is an organic material that comes from living things, such as plants and animals.
As a fuel, it is generally plant biomass, and is used to produce heat or electricity. It is a more environmentally friendly fuel source compared to fossil fuels as it does not increase the carbon dioxide in the atmosphere.
Even though burning biomass releases carbon dioxide into the atmosphere, since the plant biomass absorbs carbon dioxide from the atmosphere as it grows, the net emissions balance out to zero.
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04.05.2022 / NASA / NASA Releases Breakthrough Forest Biomass-Carbon Product
Wikipedia / Biomass