Wood-fuelled heating systems, also called biomass systems, burn wood pellets, chips or logs to provide warmth in a single room or to power central heating and hot water boilers.
A stove burns logs or pellets to heat a single room – and may be fitted with a back boiler to provide water heating as well. A boiler burns logs, pellets or chips, and is connected to a central heating and hot water system. A wood-fuelled biomass boiler could save you up to £880 a year compared to electric heating.
The benefits of biomass heating
Choosing a wood-fuelled heating system
Boiler or stove?
Boilers can be used in place of a standard gas or oil boiler to heat radiators for a whole house, and to heat the hot water. Stoves are used to heat a single room, usually in conjunction with other heating systems, but may also have a back boiler to provide hot water. Stoves are not eligible under the domestic RHI unless it is a pellet stove with a back boiler.
Chips, pellets or logs?
Chips are used to heat larger buildings or groups of houses.
Pellets are much easier to use and much more controllable than logs. Pellet boilers can run automatically in much the same way that gas or oil boilers operate. Most pellet and chip burners use automatic fuel feeders which refill them at regular intervals.
Log-burning stoves and boilers have to be filled with wood by hand and require considerably more work. You will need a lot of logs to heat a whole house, but they can be cheaper than pellets if you have a good local supply.
Do you have a local fuel supplier?
Some companies now offer deliveries of pellets anywhere in mainland Britain and Northern Ireland while the supply of logs is more variable.
Do you have space?
Wood boilers are larger than gas or oil equivalents and you will need space to store the fuel. This area will need to be somewhere that’s handy for deliveries as well as appropriate for feeding the boiler.
Do you have somewhere to put the flue?
You will need a flue which meets the regulations for wood-burning appliances. This could be a new insulated stainless steel flue pipe or an existing chimney, though chimneys normally need lining to make them safe and legal.
Do you need permission?
You may not need planning permission, but you should always check. All new wood heating systems have to comply with building regulations, and the best way to ensure this is to use an installer who is a member of a competent person scheme
Wood Pellet Boilers
All the convenience of oil. None of the carbon.
Fully automatic, pellet boilers are as convenient as oil-fired systems but much more efficient in terms of emissions. Pellet boilers use a microprocessor controller to adjust the amount of fuel and air supplied to the combustion chamber to maximise efficiency – up to 90%.
The pellets are carbon neutral because the carbon released on combustion is the same as the amount absorbed during the life of the tree. Plus, the pellets are produced from what would otherwise be waste wood – usually highly compressed sawdust.
The pellet-burner should be cleaned out around once a month, removing any small amounts of ash – which is also useful. This ash contains high amounts of minerals making it a perfect fertiliser for the garden.
Wood Pellet Stoves
Freestanding, built in and central heating models.
Automatic ignition with auto restart after brief power outages.
Built in fuel hoppers giving between 2-7 day burn times
Can be installed in most homes, using existing chimneys or prefabricated stainless steel twin wall flue systems. Ideal for modern highly insulated homes, garden rooms, conservatories, holiday homes or properties with no access to mains gas and no storage area for oil tanks.
Central heating versions can be linked into pressurised hot water storage systems and be used in conjunction with solar or ground source heating systems.
Benefits of a wood pellet burning stove
Pellet stoves are designed to heat on demand so when a room or heating system reaches the correct temperature they switch off saving fuel and giving a more comfort and better economy than traditional wood stoves. The fuel is clean to use and leaves less than .5% ash to dispose of. The wood pellets used contain only saw dust and wood chippings that are bonded together by high pressure by the woods own natural chemical Lignin and as more trees are now planted than felled this fuel is truly sustainable. You can purchase them in easy to handle single bags or bulk loads and are normally of a guaranteed quality with very low moisture content, producing more heat (5kwh/kg) per kilo than using conventional logs at (2-4kw/kg.) No need to stockpile fuels years before you use it like you need to do with tradition wood stoves. Pellets can be purchased in convenient 10kg bags or in bulk with waterproof bulk storage containers now available.