Biomass
The environmental impact of energy . A few examples

Biomass is the oldest renewable energy used by mankind. It still accounts for a tenth of the world's primary energy consumption. Most biomass comes from plants. The photosynthesis process that enables plants to grow requires solar radiation, water and carbon dioxide. Biomass stores solar energy in chemical form, which can be used when needed. The yield is low, generally less than 1% of incident solar energy in temperate countries.

The primary use of biomass is as food, but it is also used to produce energy. It is then used in the form of biofuels. When grown under glass, increasing the concentration of CO₂ by injecting this gas, increases agricultural yields.

• The wood

  Wood has been used to generate heat since man first discovered fire, probably around 500,000 years ago. As it burns, wood emits many particles and volatile organic compounds. Depending...