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What Is A Biomass Boiler?

What is a biomass boiler?

Biomass is a material, that comes from plants or even plant-based organisms. Biomass boilers are like gas and oil boilers that are found in most UK homes, except they are fuelled by solid biomass. The material used is usually either wood logs, chips or pellets. As a result, this type of boiler is bigger than others and requires more maintenance.

How does a biomass boiler work?

A biomass boiler with the latest technology has a fuel storage section, which automatically delivers the wood to the combustion area, for it to be lighted by a probe. While the fuel burns, it heats the water, through a heat exchanger.

A gas boiler is constantly supplied by the gas network, whereas an oil boiler has a large tank. However, with a biomass boiler, the fuel needs to be regularly topped up, by hand or automatically. A hopper is an automatic mechanism, which enables a higher volume of fuel to be stored. It can also refuel the boiler when needed, creating less work for you. However, due to the solid fuel involved, a biomass boiler still needs to be emptied and cleaned. The frequency in which you are required to do this depends primarily on the level of technology in the boiler.

Why biomass?

As most popular boilers work by burning fossil fuels, carbon emissions are released into the atmosphere. With the UK government envisioning 2050 as the year, whereby the country achieves net-zero, there needs to be a realistic, cleaner, heating alternative.

Burning wood to heat homes is a carbon-neutral process. This is because, it produces the same amount of carbon dioxide as the tree absorbed when it was growing, essentially, cancelling itself out.

When compared to other types of boilers, biomass is a strong competitor. Like gas and oil boilers, biomass boilers can achieve high levels of energy efficiency, meaning very little energy is wasted. This is good news for homeowners, as it means they avoid a drop-off in quality while heating their home in an environmentally friendly way.

What Fuel Does a Biomass Boiler Use?

A biomass boiler uses organic material as fuel, typically including:

Wood pellets

When sawdust and wood shavings are put together, they form small pellets. Wood pellets are the most popular type of fuel for biomass boilers because their compact size means they can be burnt automatically. As they have a higher calorific content, they are more efficient than wood chips or logs.

Wood chips

Wood chips were previously logs, that were fed through wood chipping machines. Due to their simplicity, wood chips are cheaper to buy than pellets. However, cost aside, they are not always the best option for domestic boilers because they are bigger in size. This increases the cost of transportation and makes them harder to store. They also have a higher moisture count than wood pellets, making them less efficient.

Wood logs

Only some biomass boilers can be fuelled by logs. This is a good option for homeowners who have access to waste wood near their homes, as it can massively reduce fuel costs. However, like wood chips, they have a high moisture count, meaning they don’t deliver as much energy as wood pellets.

Agricultural Residues

By-products from farming and crop production, such as straw or husks, though less common in residential settings.

Costs, savings and financial support for biomass boiler

The cost of a biomass boiler for an average home is around £18,000, including installation. However, the cost can vary depending on the size and type of the boiler. The price of biomass fuel can also vary, but after the initial investment, biomass boilers can save up to £1,100 a year compared to an old electric heating system. By replacing an old electric heating system, it’s possible to save as much as £880 per year.

However, the UK government provides grants and schemes for biomass boilers to support the adoption of biomass boilers. For instance, the renewable heating incentive scheme (RHI) has closed, but existing members need to maintain compliance to receive remaining funds. The boiler upgrade scheme (BUS) in England and Wales offers a grant of £5,000 for biomass boilers to help consumers overcome the high upfront cost of purchasing and installing a biomass boiler.

Additionally, the renewable heat premium payments scheme offers a grant of £2000 per property to help with the initial costs, which then gets deducted from the RHI payments over the seven years of the scheme.

Warma UK is dedicated to improving home energy efficiency and helping to lower energy expenses. Check your eligibility now to take advantage of this opportunity.

See if you're eligible for free biomass boiler grant

See if you're eligible for free biomass boiler grant

Michael Cornish