Biomass Burners - Wood Burning Stoves

Biomass is living and recently dead biological material that can be used for fuel. It consists of plant matter, animal by-products and general waste products. If biomass originates from a sustainable source then it can be considered as a renewable energy

Fossilised Fuels

Biomass excludes any organic material which has been transformed by biological processes into fossilised fuel, such as coal and petroleum. Although fossil fuels were originally created from biomass, they are not generally considered to be biomass because they contain carbon that has been outside the carbon cycle for a considerable length of time.

Biomass Fuel for Heating

Wood fuel is one of the most environmentally friendly ways of heating individual rooms or a whole house, because timber is carbon neutral fuel. Wood fuel is readily available as logs, wood chips, bark, sawdust and wood pellets. Wood can also be obtained by coppicing, whereby wood is removed in rotation from young willow and poplar trees.

Biomass Burners - Domestic Wood Burning Stoves

Wood burning stoves are typically sealed units manufactured from either cast iron or steel.  They operate at around 75 per cent efficiency whereas an open fire operates at only 15 to 20 per cent efficiency. Wood burning stoves require regular feeding  with good quality, clean, dry wood.  

Biomass Burners - Wood Burning Water Boilers

To provide heating and domestic hot water a log fired stove with a combined boiler is required. Wood burning stoves with back-boilers can provide most of the required domestic hot water in a house. Larger models are capable of supporting domestic central heating systems and are very cost effective. Wood burning stoves will usually have an output of 6-12 kilowatts . Those connected to central heating and hot water system are generally bigger, at 15 kilowatts.

Biomass Burners - Wood Pellet Boilers

Wood pellet boilers are a recent development for wood fired pellet heating and range in output from 15 kilowatts to over 500 kilowatts outputs. The wood pellets themselves are made from the by-products of saw mills. The domestic boiler systems are computer controlled to optimise combustion and achieve efficiency levels of around 90 per cent. To overcome the problems of wood storage and regular feeding most pellet boilers incorporate automatic pellet feed hoppers which only require re-filling every 2 to 3 days.

Wood Burning Stoves - Clean Air Act – Smokeless Zones

Wood burning stoves can be used in areas that are not smokeless zones. In areas that are smokeless zones, wood can only be burnt on appliances that are exempted under the Clean Air Act.

Planning Permission for Wood Burning Stoves

Planning permission may be required for a new chimney or flue. In these circumstances it is advisable to discuss the proposals with the local planning authority before having a system installed.

Building Regulations and Wood Burning Stoves

Wood burning stoves, wood burning boiler systems, chimneys and flue installations must all comply with the Building Regulations. It may therefore be necessary to consult the Local Authority, Building Control Service.

In most circumstances, where a competent person such as a HETAS (Heating Equipment Testing and Approval Scheme) registered installer is employed to carry out the work, it may not be necessary to involve the Building Control Service. This exemption will usually apply where the building is less than three storeys and where the solid fuel burning appliance is less than 50 kilowatts. It may also apply where heating and hot water service systems are connected to a solid fuel burning appliance.

Wood Burning Stoves - Installation Costs

The cost of a wood burning stove generally depends on the size and type of system chosen. The installed cost of a stand alone room heater is generally between £200 and £4,000. A wood pellet boiler to serve an average sized three bedroom semi-detached house will be about 20 kilowatts and will typically cost between £5,000 and £14,000.

Wood Burning Stoves - Running Costs

Fuel costs are largely dependant on the distance from the wood supplier. Wood is typically up to 30 per cent cheaper than oil or gas and there are considerable environmental benefits if the wood is sourced locally.

The length of the payback period will depend on the fuel being replaced and the type of wood fuel being used. Payback will be more favourable in an area that does not have a natural gas supply network