Through the process of photosynthesis, chlorophyll in
plants captures the sun's energy by converting carbon dioxide
from the air and water from the ground into carbohydrates,
i.e., complex compounds composed of carbon, hydrogen, and
oxygen. When these carbohydrates are burned, they turn back
into carbon dioxide and water and release the sun's energy
they contain. In this way, biomass functions as a sort of
natural battery for storing solar energy.