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What are they?
Biomass (also known as bio energy or bio fuel) is the general term for natural or 'organic' fuel sources where the plant material which makes up a biomass fuel source, died relatively recently.
This is what makes biomass different from fossil fuels such as coal, which are the remains of plants that lived millions of years ago.
Biomass is classed as sustainable rather than a renewable energy source as producing energy from biomass releases carbon dioxide into the atmosphere. The principle behind biomass is that as a tree grows it absorbs carbon dioxide (which it stores in its woody tissue) and when the wood is burned, the same amount of carbon dioxide is released back into the atmosphere, making the process carbon neutral.
See Carbon Footprint for more information about carbon dioxide in the atmosphere.
The technology
Biomass fuels can be either woody (eg wood chips) or non-woody (eg animal waste). Small-scale biomass systems usually take the form of boilers or stoves and use fuels including wood chips, wood pellets and logs.
Wood pellets are made by compacting wood products so they provide more energy than a non-compacted wood fuel. They also contain less moisture than other wood products (as water and sap stored within the wood is released the wood is compacted into pellets) meaning they burn more efficiently.
This helps to ensure that no harmful partial combustion products (such as carbon monoxide) are produced. This can mean that wood pellets are slightly more expensive than wood chips or logs.
Biomass stoves are 'stand-alone' and usually provide heating for a single room (usually the main living area). If you require an automatic-feed system, the only suitable fuel is wood pellets which feed the stove with pellets directly from a hopper or silo (manual feed systems usually need to be fed by hand every day).
Stoves can provide a significant amount of heat (between six and 12kW) and with some systems, it is possible to attach a back boiler for hot water heating (for direct use or for space heating using radiators). The effectiveness of a biomass stove can be up to 80 per cent and can provide significant amounts of heating in well-insulated properties see Energy efficiency.
Biomass boilers are connected to the central heating and hot water systems and can provide heating for an entire property. It is also possible to purchase boilers with an integrated hot water storage tank.
One important issue to consider if you are thinking of installing a biomass boiler or stove is the storage space needed for a supply of wood pellets, wood chips or logs. To make sure that your biomass stove or boiler is as sustainable as possible, it is important to look for a local supplier as this helps to reduce the carbon dioxide emissions caused by transporting the fuel. There are several local companies which produce biomass fuels, details of which can be found at www.nef.org.uk/logpile
It is also important to check that the vent material in your flue has been specifically designed for use with appliances that use wood as a fuel. Chimneys that do not meet this requirement can have a lined flue fitted, however, you may need to obtain planning permission for this work (for more details please see the planning section of this pack). In addition, any new installation must comply with both current Building Regulations (Part J) and the Clean Air Act. Most biomass fuels are smokeless and so comply with these criteria.
Lifespan and warranty
Biomass boilers and stoves require more regular maintenance than gas or oil boilers (mainly removal of ash) and cannot be used when cleaning is in process. It is possible to purchase 'self-cleaning' appliances which help to maintain the efficiency of the system. An accredited installer will be able to advise you on the proper method and equipment needed (if any) for cleaning your boiler or stove.
Warranties vary from 12 months to five years and individual components of the system may carry their own warranty. It is always advisable to ask an accredited installer about the warranty of the system. Like standard boilers and stoves, biomass boilers and stoves require an annual check by a trained engineer.
Cost
The Department of Trade and Industry currently give average system prices as between £2,400 and £2,600 for a biomass stove and approximately £4,500 per 15kW for biomass boilers. It should be noted that although they are often much more convenient, automatic feed wood pellet systems can be more expensive.
Also, unlike other renewable technologies, using biomass does mean that you still pay for your fuel. Wood pellets (the most expensive biomass fuel) cost between three pence and 3.5 pence to generate one kW of energy compared to approximately 10 pence per kWh for electric heating systems and 2.8 pence per kWh for efficient gas boilers. The continued increases in the price of gas and electricity will make biomass an increasingly cost effective option.
Where in the district?
Biomass heating systems can be installed successfully in all areas of the South Derbyshire District. People switching from electric or oil heating often experience the biggest cost savings after installing a biomass boiler or stove, making biomass particularly suitable for areas of the district off the gas network. Wooded areas and areas close to local suppliers may also benefit from reduced delivery costs.
Contact details
South Derbyshire District Council
Energy Officer
Civic Offices
Civic Way
Swadlincote
DE11 0AH
Tel: 01283 595974
Online: Contact Form
email: energy@south-derbys.gov.uk
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