540 Clean Energy
Biomass Energy
In many countries, biomass (waste material from plants and animals) is a
common household energy resource. The energy in biomass materials can be
released by burning it or by allowing it to rot
and produce biogas (a natural gas).
Common sources of biomass energy
Biomass from plants is renewable, but when it is burned as fuel it contributes
to global warming and health problems. When you make a fire with wood or
cow dung, you are using biomass energy on a small scale.
On a larger scale, crop wastes (residues) can be used to generate electricity.
In Cuba, for example, a large amount of electricity is generated by burning
sugarcane stalks after they have been harvested and milled for sugar. Rice
husks, wood waste, and other kinds of biomass can also be used in this way.
While it may be renewable, pollution from burning crop wastes is bad for the
health of the community and the environment.
Biogas
Biogas is produced when organic matter rots. When biogas is captured in a
closed container, it can produce a small flame for cooking, or electricity for
heating, lighting, pumping water, and operating motors and farm equipment.
By converting the organic matter in human, animal, and plant waste into
energy, biogas turns waste products into a resource that is good for the
environment and for community health. Biogas can be made from many kinds
of organic matter:
• animal manure and urine
• human feces and urine
• food waste such as meat, blood, bones, and vegetable scraps
• plant matter such as crop residues, straw, leaves, bark, branches, and
grass cuttings
A Community Guide to Environmental Health 2012