There are so many benefits of using wood fuel. But burning wood the wrong way, or using the wrong type, is wasteful from both an economic and an environmental perspective. Following a few simple tips can help save our planet and the pennies in your pocket.
- Use dried, fully seasoned chopped wood logs with a moisture content of less than 25%. The higher the moisture content, the lower the amount of available energy. Wood that is well seasoned is darker and makes a distinctive hollow ‘clack’ rather than a dull ‘thud’ when knocked together. It also feels lighter than an unseasoned log. The bark should be peeling away with cracking of the wood around the outside. Seasoning to this standard takes between 18 and 24 months. During seasoning, logs are stacked neatly off the ground with plenty of space between them for air movement. A store with slatted or woven sides is ideal for air movement, but should be covered against rain. In addition, an orientation to allow maximum exposure to the sun is ideal.
- Store the wood protected from the weather in a log store or under a suitable cover. As with the recommended storage arrangements for seasoning, allowing for air movement and sun exposure will help keep your stored logs dry.
- Burn the seasoned wood briskly with plenty of air. A stove pipe thermometer gives a really good indication that you are getting the best out of your stove. Don’t be tempted to close the air vents down to keep the fire in overnight, as this will only lead to inefficient combustion, potentially damaging your flue.
- Consider investing in a wood moisture meter to test the moisture content of wood before you burn it. It will help you burn wood more efficiently and will pay for itself before long.
- Hardwoods have a greater density than softwoods, which can provide you with more heat output by as much as 30%.
- Softwoods are often cheaper and easier to source. Conifer is a great wood to burn and only needs to be dried for approximately 12 months.
- Use the correct size, quality, and moisture content of chip for your boiler, as every boiler is built for a specific size chip. Many boilers also specify an optimum moisture content level, which can be even lower than the 25% we suggest.
- Buy chips by cubic metre. Hopefully you won’t be getting wet chips, but if you buy by weight you’ll be paying extra for any moisture present in the wood.
- Chips made by most tree surgeons are not suitable as they are not seasoned, contain chopped up leaves, and many of the chippers they use are not designed to make the right size of chip.
- Pellets have a larger environmental footprint than logs or chips. They track the price of fossil fuels much more closely which can leave you open to cost fluctuations.
- They take up less storage space and are much more energy dense.
- Some automated systems work better with pellets (or only work with pellets) since they flow more easily due to their uniform shape and size.
Choosing a heating system
Even if you buy your wood rather than gathering the timber from your own woodland, you can expect to save money on your heating compared to electricity by installing a woodburning heating system.
- The most inefficient form of wood heating – as low as 5%. This is largely due to an uncontrolled draught up the chimney.
- Enclosed, these are between 50-75% efficient.
- Stand-alone room heaters.
- Burn logs or wood pellets.
- Can be fitted with a back boiler to heat your water.
- The output from one of these can be excellent and they will heat your rooms up nicely. This type of burner also looks very attractive and there are a variety of different models available.
Gasification batch log burner
- Up to a whopping 90% efficient.
- Used to heat large properties like farmhouses and B&Bs.
- Burn logs, pellets, or wood chip.
- Connect directly with your hot water and radiators.
- Some have a special fuel feeder, which will automatically refill with chips and pellets as required.
- Tend to be quite large systems requiring more space, and are better suited to outside locations or basements.
Other things to consider
Do you need planning permission?
If your home doesn’t have a suitable flue you will have to build one, or ensure that your existing flue is in good order. If you already have a chimney then this is an easy option. If you have to build a new one you may have to apply for planning permission. Check with your local council to see if this applies.
Are there any regulations?
Certain areas of the UK are smokefree zones where wood can only be burned in certain appliances. It’s always good to check what the regulations are surrounding the use of woodburners in your area. Contact your local Council’s environment department, or the Environment Agency.
Are there any grants available to you?
The Renewable Heat Incentive was launched by the government in June 2011, and may help you to pay for the installation of a woodburner, especially in business situations. Please see our page on Funding & Grants for more information on this and other schemes.