Biomass is biological material made from living, or recently living organisms. It is the oldest source of renewable energy, used since our ancestors learned the secret of fire. Biomass is essentially carbon, hydrogen and oxygen based. Biomass energy is derived from five distinct energy sources: garbage, wood, waste, landfill gases, and alcohol fuels.

Used as an energy source to produce heat or in modern times electricity directly, or converted into other energy products such as bio-fuel.

One thing for sure, biomass is a green energy source because it uses renewable resources to produce energy. This means that we will have an endless supply of biomass just like the sun and the wind. The biggest challenge is perhaps to find a suitable land with a sufficient water supply to make the system work. When water is not abundant, it is very difficult to rely on biomass technology to generate energy.

Until recently, biomass supplied far more renewable electricity than Solar or Wind, as the most common way to capture the energy from biomass was to burn it to make heat. The most common way of converting biomass to electricity is to burn it to produce steam, which turns a turbine that produces electricity.
The problems with direct combustion of biomass are that much of the energy is wasted and that it can cause some pollution if it is not carefully controlled. One way to offset this downside is by planting more crops which will be a great help to reduce the amount of carbon dioxide in the atmosphere.

It is a good idea if you can use organic waste to produce electricity. This is the key that makes biomass different than other green energy sources. When biomass is used extensively, the government can save a considerable amount of money for reduction in waste disposal. Furthermore, they can reduce their dependency toward foreign oil to power their plants.

The growth of bio-power will depend on the availability of resources, land-use and harvesting practices, and the amount of biomass used to make fuel for transportation and other uses. However, like Hydro generated energy there are some environmental impacts and risks, that come with the benefits.

The main impacts and risks from biomass are sustainability of the resource use, air quality and carbon emissions.