Wood Chips: Are They A Good Fuel For Your Biomass Boiler?

Biomass boilers usually run on wood logs, chips or pellets. When the wood is burned in the boiler it produces heat that is used to create hot water.

Wood is considered a renewable fuel. So if you install a biomass boiler you could benefit from the government’s Renewable Heat Incentive scheme and reduce your carbon emissions.

If you’re thinking about installing a biomass boiler, you need to work out what kind of installation you need. A good way to do this is to start by considering which fuel you’d like to use. To help you make this decision we’ve made a list of the pros and cons of one popular biomass fuel: wood chips.

Pros

High energy density

Wood chips tend to be the most energy-efficient biomass fuel as they produce more kWh per kg than wood pellets and logs. So in terms of how much energy they produce when burned, wood chips come out on top.

Some types compatible with automatic feeding systems

Lots of people want a biomass boiler with an automatic feeding system as they require less attention than boilers that need refuelling on a regular basis. An advantage of wood chips is that some of them are compatible with automatic boiler feeding systems. If you want these, you’ll need to make sure you buy chips that are a uniform size and shape.

Need less storage space than logs

Another advantage to wood chips is that they need less storage space than logs. On average, 1 tonne of wood chips takes up just over 2m³. Logs, however, need double this amount of storage space to allow them to dry out. So wood chips are a better option if you have limited fuel storage space.

Cons

Uneconomical for smaller installations

Unfortunately, using wood chips to power your biomass boiler is usually uneconomical if you have an installation smaller than around 40-60kW. Wood chips can be difficult and expensive to transport and store, partly due to their high moisture content. Many manufacturers don’t produce chip-fuelled boilers smaller than 40kW because these difficulties mean that there isn’t a demand for them. Wood pellets are more commonly used to power smaller domestic biomass boilers.

If you decide that wood chips could be the best biomass fuel for you, a good next step would be to get the opinions of a few reliable boiler engineers. They will be able to give you advice on which biomass boilers could be best for you.

Price

Approx. £7,000-£12,000

Installation time

3-4 days


Advantages and disadvantages
  • High energy density
  • Some types compatible with automatic feeding systems
  • Needs less storage space than logs
  • Uneconomical for smaller installations