Biomass is a term for all plant and animal material. Biomass has been used as an energy source for hundreds of years. Many kinds of material can be combusted or digested to make energy but biomass can only be considered as a renewable energy if it comes from a sustainable source:

• Energy Crops: Crops grown specifically to be used as a source of energy.
• Agricultural By-products: The use of animal slurries, litters and residues to produce energy.
• Forestry by-products: arboriculture by-products, sawdust.

Biomass is currently the largest source of non-fossil fuel energy supply, providing 13% of primary energy demand worldwide.

There are a number of technologies that can be used to extract the energy from biomass. The biomass can be burned directly to extract heat; it can undergo pyrolysis or gasification to produce fuel in other forms (such as char, oil or gas); the oil in the biomass (usually seeds) can be extracted and burnt. The gas produced can be burnt in a CHP unit to produce heat and electricity although this technology is still in development.

At the most simple level, wood can be combusted in a variety of kinds of stoves for space (and sometimes water) heating. A community heating system can be installed, which means that one unit need be installed. (The boiler system would be modular with a gas-fired boiler for use during maintenance or as a top-up when demand is high.)

Biomass technology can be considered to be carbon neutral, as the carbon absorbed when re-growing balances the carbon released when burnt. Coppiced plantations can actually absorb more carbon dioxide than mature trees - since carbon dioxide absorption slows once a tree nears maturity.

Easy to control, biomass can be converted into useful electricity or heat as required; it is not dependent on other factors such as whether there is wind.

The requirement of a fuel supply can help stimulate the local economy.

A reliable fuel supply needs to be established. Space is required for fuel storage and the plant room (unit, hot water storage etc.).

Automated, clean-operating systems are now on the market but the units will still require regular maintenance.

There are many different types of stove available. They can range price from £275 upwards, depending on the size and type of stove.

Please email or call CEN on 020 8683 6694 for further information or advice.