Judith’s pellet boiler stove
Judith’s pellet-fired boiler stove
Judith has installed a wood pellet boiler-stove. This compact appliance heats her five-bedroom house using sustainable wood pellet fuel without having to worry about lighting fires.
Heating with wood pellets – made from compacted sawdust – is a very controllable way of using wood fuel. Judith’s pellet boiler keeps the fire going automatically and she programs it using an electronic controller.
A convenient alternative
Judith opted for a pellet boiler as a convenient, efficient and climate-friendly heating option. Some of the heat goes directly into the room as warm air, but most of the output is hot water for the central heating. The boiler feeds radiators and the hot water cylinder in the house. Just as with a gas boiler, her heating system is programmed with an electronic controller. The pellet boiler automatically feeds the fire and uses microprocessor-controlled fans for optimum efficiency.
Bag-by-bag or in the hopper
Judith fills her boiler manually by pouring pellets from a 15kg bag directly into the top of the boiler. An alternative would be to use a larger pellet boiler that is fed automatically from a hopper. Pellets can be delivered by truck and pumped into the hopper, so it’s possible to use this form of wood heating without any manual work at all!
Judith estimates a 15kg bag of pellets is enough to heat the house for one or two days during the heating season. In the winter of 2008/09 she used a total of 1000kg of pellets (67 bags, around 4900kWh of heat energy). A typical UK household could need twice or three times that much. Pellets bought in bulk should cost around 5p per kWh of heat – comparable to mains gas, and cheaper than LPG or electricity.
Financial and environmental benefits
Judith paid around £4,000 for her boiler and got a £1,500 grant through the Low Carbon Buildings programme that was running at the time. A pellet boiler system of this type is now eligible for support under the Renewable Heat Incentive (RHI).
Wood is a renewable source of energy. Using wood for heating can be a good way to reduce carbon emissions if it is sourced from sustainable forestry – where a new tree is planted for every tree that is cut down. Greenhouse gas emissions for pellets are around 90% lower than for oil or gas, so installing a wood heating system can reduce your household carbon emissions by several tonnes!