What is a biomass boiler?

With the world trying to be greener and more climate considerate, biomass boilers are becoming a popular option for lowering carbon emissions. There are plenty of benefits for using a biomass boiler, but also some downsides. So, what is a biomass boiler? Continue reading to find out everything you need to know about biomass boilers.

What is a biomass boiler?

A biomass boiler is like a standard boiler, but is fuelled by biological materials that come from plant-based organisms, like wood chippings, pellets or logs, rather than oil or gas. For this reason, it is much bigger than a traditional boiler and requires a lot more maintenance.

Biomass boilers still heat up your whole house, including the water, but instead of burning oil or gas, they burn natural resources instead. This provides a much smaller carbon footprint, and has been known to produce an efficiency of up to 91%. This is similar to even the best high-efficiency boilers on the market.

How does a biomass boiler work?

Biomass boilers work very much the same way as traditional boilers, combusting fuel to produce heat that is then used to heat water. However, they differ from their fossil fuel-burning counterparts by burning sustainable materials, such as wood pellets and chippings. Because of this, biomass boilers are much larger than traditional boilers in order to hold a larger volume of fuel. 

Modern biomass boilers have a fuel storage compartment that  stores and automatically feeds wood pellets into the boiler, leading to a more infrequent need to manually fill it up. As the fuel burns, it heats the water via the heat exchanger.

While gas boilers have a constant supply from an energy company, a biomass boiler must be constantly replenished and  can require a little more maintenance. As it burns solid fuel, a biomass boiler needs to be manually emptied of ash and cleaned regularly – again, incurring more maintenance time.

This maintenance could range from once a year to once a week, depending on the type of system you have.

What types of biomass fuels are there?

There are three types of biomass fuels you can use to feed your boiler and heat up the house. They are:

Wood pellets

Pellets are made of compacted wood shavings and sawdust. They are much easier to transport and store compared to chips and logs because of their smaller size and moisture content being around just 8%. Pellets are the most popular form of fuel used for biomass boilers because their size makes them the best for feeding automatically from a hopper into a burner, reducing manual workload.

Wood chips

Logs are fed through wood chipping machines to  create wood chips. They are cheaper to buy compared to wood pellets because they are easier to produce. Wood chips are not the best choice for using a biomass boiler, though, as they take up more storage space and have more moisture content (around 25%), so work less efficiently.

Wood logs

Not all biomass boilers can be fuelled by logs, but the ones that can are an attractive option to households with access to waste wood. For example, they’re more suited to a house that’s located close to a forest where wood can be collected for free.

Wood logs are not ideal for burning, though, due to a 25% moisture content, and they deliver relatively little energy compared to wood pellets. Pellets can also be automatically fed into the biomass boiler, whereas logs must be manually handled and take up much more storage space.

What are the benefits of a biomass boiler?

The main benefit to using a biomass boiler is its impact on the environment. A traditional gas-burning boiler is effective in its use, and the most popular option in the UK, but it emits carbon dioxide into the atmosphere. Carbon dioxide stops heat leaving the planet, which increases the overall temperature and worsens the climate crisis.

A biomass boiler burns wood, which is a carbon neutral process. This means it only produces the same amount of carbon dioxide as the tree absorbed while it was growing. It is a sustainable source of energy, and doesn’t take millions of years to form.

In addition, there are millions of tonnes of waste wood filling land every year in the UK. With so much sustainable material available, biomass boilers offer a planet-friendly alternative to traditional boilers.

What are the negatives of a biomass boiler?

As positive as biomass boilers can be, they are not perfect. Of course, they take a lot more maintenance to care for than a traditional boiler and actually cost a lot more too.

Installing a manually fed log boiler may cost somewhere between £4,000 and £10,000, while an automatically fed pellet boiler can be anything from £9,000 to £21,000. Considering a traditional boiler typically costs under £2000, it is clear to see why they’re so popular in comparison to biomass boilers.

Biomass boilers do also release carbon monoxide, so ensure you have a detector installed.

Boilers at Toasti

If you require any further information about biomass boilers, do not hesitate to get in touch with us here at Toasti. We provide a wide range of services, including boiler cover, installation and boiler services for expert maintenance. If you’d like to contact us, call us on 0161 527 7326, or email us at info@toasti.co.uk.