Given the dramatic increase in energy prices and ongoing concerns about environmental sustainability, it’s unsurprising that many homeowners are exploring alternative ways of heating their homes.
Installing a biomass boiler is one way to reduce your long-term energy bills and your environmental impact. These boilers use non-fossil fuels from sustainable sources in order to heat your home.
In this article, we look at how much biomass boilers cost, what affects the cost of installing a biomass boiler, and ways you can save money. We also look at the costs of running a biomass boiler, some advantages and disadvantages of using a biomass boiler, and how to find a professional to fit and install one.
Topics
How Much Does a Biomass Boiler Cost?
Biomass boiler costs depend in part on the type of fuel you plan to use, and how the fuel is fed into the boiler.
The table below explains the estimated cost of different biomass heating systems:
| Biomass Boiler Design | Estimated Supply and Installation Costs | Time Required |
|---|---|---|
| Log Boiler | £6,000 to £12,000 | 1 to 2 days |
| Wood Chip Boiler (manually-fed) | £4,000 to £10,000 | 1 to 2 days |
| Wood Chip Boiler (automatically-fed) | £10,000 to £25,000 | 1 to 2 days |
| Pellet Boiler (manually-fed) | £5,000 to £10,000 | 1 to 2 days |
| Pellet Boiler (automatically-fed) | £10,000 to £25,000 | 1 to 2 days |
As shown in the table above, biomass log boilers can cost anywhere from £6,000 to £12,000. In most cases, installing a log-fuelled boiler is a straightforward process and should take just one or two days.
If you plan to use wood chips, the cost varies depending on whether you want to feed the woodchips into the boiler, or whether you prefer an automatic system. The cost of manually-fed wood chip boilers ranges from approximately £4,000 to £10,000.
If your budget allows, an automatically-fed wood chip boiler typically costs between £10,000 to £25,000. Both variants take between one to two days to install.
Pellet biomass boilers are a sustainable and efficient way to heat your home. If you don’t mind occasionally topping up an auger or hopper, you can purchase a manually-fed pellet boiler for £5,000 to £10,000.
As you might expect, biomass boilers with an automatic pellet feeder are more expensive and could cost you as much as £10,000 to £25,000.
As with the other types of biomass boilers, the pellet versions usually take between one and two days to install.
What Affects the Cost of a Biomass Boiler?
As we saw above, biomass boiler costs can vary quite considerably. In this section, we take a more detailed look at the factors that influence the overall cost of installing a biomass boiler.
The Size of Your Home
Unsurprisingly, the size of your home has a direct impact on the overall cost of the biomass boiler you need. This is because you’ll need a more powerful boiler to effectively heat your home.
The size of your home can also affect the overall cost of running your biomass boiler. In particular, you may need to run your boiler for slightly longer than average in order for every room in your house to reach the desired temperature.
Boiler Output and Design
Biomass boiler costs also depend on the output and design of the boiler.
If you’re going to invest in a biomass boiler, it makes sense to choose a model that is powerful enough to effectively heat your home—whether it’s a 2-bedroom bungalow or a sprawling estate.
However, the higher the output of your boiler, the more expensive it’s likely to be.
To determine what output you need for your home, you need to consider the size of your home and your energy consumption. Domestic biomass boilers usually range in output from 15 to 56 kilowatts (kW). A 15 kW biomass boiler should comfortably heat a one- or two-bedroom home.
The cost of your biomass boiler also depends on the design.
As shown in the price comparison table above, biomass boilers can be manually fed or automatically fed. While log biomass boilers are always manually fed, wood chip or pellet boilers have both manual and automatic feeding options.
Automatically-fed boilers can be fed through an integrated hopper or auger (which you must top up yourself using bagged pellets or wood chips), or through a separate aboveground or below-ground storage unit (which allows you to buy bulk quantities of pellets or wood chips).
In terms of size, pellet boilers are generally more compact than wood chip boilers. Wood chip boilers are often bigger than pellet boilers due to the bulky auger which feeds the chips into the boiler.
Further to these options, there are also pellet stoves, which are among the more affordable choices for biomass heating, and are especially suited to smaller homes.
Your Choice of Fuel
Your fuel choice will be dictated by the type of biomass boiler you opt for – and the different sources carry varying costs.
Logs
Though the cost of logs is more affordable than pellets or wood chips, it’ll require more effort on your part, as the logs must be manually fed into the biomass boiler—usually every day.
Logs are usually sold by cubic metre, rather than by tonne. The cost ranges from £80 to £200 per cubic metre depending on the species of timber you choose.
Hardwoods – especially oak, beech, ash, and birch – are denser, and will therefore burn longer than softwoods like pine. For more information on how to choose logs for your biomass boiler, see this Forestry Commission guide.
Wood Chips
Wood chips can also be an affordable source of biomass fuel—particularly if you live in a rural area and you can fell your own trees.
However, to do this, you’ll need a fuel-grade chipper to turn the timber into biomass. Alternatively, hiring a chipper generally costs around £200 per hour, plus travel time.
If you can’t source your own wood chips, buying wood chips could cost you between £80 to £110 per tonne, depending on the supplier and delivery method.
Wood Pellets
Pellets are much denser than logs and wood chips, and so they’re the most efficient fuel choice for biomass boilers. In fact, pellets can hold up to 3.5 times more energy.
This also makes them the most expensive type of biomass fuel. Pellets usually cost anywhere from £160 to £225 per tonne.
The cost varies depending on whether the pellets are tipped out onto your property (less expensive), delivered into your storage unit using a blown system, or delivered to you in bags (most expensive).
The Quantity of Fuel You Need
To calculate how much biomass fuel will cost you per year, you should divide the output of your biomass boiler by 4. So, if you have a modest 15kW biomass boiler, you’ll need approximately 3.75 tonnes of fuel per year (depending on your choice of fuel and energy consumption).
This means that you could spend approximately £300 to £410 per year on wood chips, or £600 to £840 per year on pellets.
For log boilers, fuel is sold by the cubic metre, not by the tonne. To convert tonnes of fuelwood to cubic metres, simply multiply by 1.38. For a 15kW log boiler, you might spend between £410 to £1,035 per year on fuel depending on your choice of timber.
Whichever fuel you choose, you should only purchase biomass fuels through a supplier that is certified by HETAS or Woodsure. This ensures that your fuel is high quality, and doesn’t contain too much ash or harmful contaminants that could gum up your boiler and pollute the air.
To find a reputable supplier, search the government’s Biomass Suppliers List.
Fuel Storage
In addition to the cost of buying your boiler and fuel, you’ll need to sort out a way to store your fuel.
A proper biomass fuel storage system is important to keep the fuel dry (since wet logs, chips, or pellets are useless) and to keep dust at bay. Outside dust can clog up the inside of your boiler, reducing the efficiency of your boiler and potentially higher servicing costs.
Depending on which fuel you use and how much you need to store, you may be able to use an auger, a hopper, or an aboveground or below-ground storage system.
Adapting Your Existing Heating System
If you plan to switch your existing heating system to a biomass boiler, you may need to make certain adjustments.
For example, if you don’t currently have a hot water cylinder, you may need to buy one so you don’t have to wait for hot water. This can cost between £850 and £3,500 depending on brand and size.
It may also be necessary for you to have new radiators and pipework installed – which is something your heating specialist will be able to advise you on.
Maintenance and Servicing Costs
Burning biomass logs, wood chips, or pellets creates ash – but if you buy high-quality fuel, your boiler should produce less ash. You’ll need to empty the ash can every one to four weeks.
There are uses for the ash – one being that you can use the ash as fertiliser!
A biomass boiler service can cost between £180 and £450, depending on the output of your boiler, the type of fuel you use, and your location. At a minimum, biomass boilers need to be serviced at least once a year, and possibly more often depending on how much you use them.
How Can I Save Money on a Biomass Boiler?
We can quite easily see how the costs can stack up for biomass boilers – but thankfully, there are some ways to reduce those fees over time, or to incentivise installation with predicted returns from the Renewable Energy Incentive.
Consider Manually-fed Biomass Boilers
This suggestion will come as no surprise – they’re more cost-effective, but they will cost you more in time – considering manually-fed biomass boilers will save you around £15,000 in your initial setup and installation fees.
They will of course need your attention for filling (something which you don’t need to think about with automatically-feeding alternatives), and the drawbacks are yours to decide here.
Look For Secondhand Biomass Boilers
Occasionally, homeowners and businesses may want to decommission their existing biomass boilers. Only a small number of retailers offer used biomass boilers, but it could be worth investigating given that biomass boilers require a significant financial investment.
If you’re considering a secondhand biomass boiler, do your research and check the following:
- How much will it cost to install compared to a new biomass boiler?
- Is the manufacturer’s warranty still valid? For how long?
- What RHI tariff will I receive?
Energy Savings
Choosing a biomass boiler is an investment, but it’s worth looking at how much you could save by switching to biomass. This table only relates to potential savings in England, Wales, and Scotland:
| Your Current Heating System | Potential Savings from Switching to Biomass | Potential CO2 Savings from Switching to Biomass |
|---|---|---|
| Older Gas Boiler (G-rated) | £445 to £450 | 5,500 to 5,800 kg per year |
| Newer Gas Boiler (A-rated) | -£180 to -£210 | 2,900 to 3,050 kg per year |
| Older Electric Storage Heater | £1,270 to £1,350 | 3,900 to 4,150 kg per year |
| Newer Electric Storage Heater | £700 to £730 | 2,800 to 2,950 kg per year |
| Older Oil Boiler (G-rated) | £425 to £440 | 8,500 to 9,000 kg per year |
| Newer Oil Boiler (A-rated) | -£265 to -£295 | 4,500 to 4,750 kg per year |
| Older LPG Boiler (G-rated) | £1,360 to £1,420 | 6,600 to 6,900 kg per year |
| Newer LPG Boiler (A-rated) | £355 to £360 | 3,550 to 3,700 kg per year |
| Coal | £380 to £395 | 11,300 to 12,000 kg per year |
Please note this guide is for your information only. The figures above are based on converting an existing heating system to a pellet biomass boiler in a 4-bed detached house with basic insulation. Source: Energy Savings Trust.
As you’d expect, the biggest savings happen when you’re switching from older heating systems (such as older gas, oil, or LPG boilers) than when switching from newer systems. In fact, switching from a newer A-rated gas or oil boiler to a biomass boiler could end up costing you money.
Though switching to a biomass boiler can be more expensive in some cases, it’s also worth considering how a biomass boiler can reduce your carbon footprint. Changing to a biomass boiler substantially reduces the amount of carbon dioxide (CO2) that’s produced as a result of heating your home—especially if you switch from an older gas, oil, or LPG boiler or from coal.
If reducing your carbon footprint is important to you, switching to a biomass boiler or installing one in your new home is a great way to lower the environmental impact of heating your home.
In Northern Ireland, switching to a biomass boiler can save you between £110 and £1,950 per year—unless you have a newer (A-rated) oil boiler. In that case, switching to a biomass boiler could cost you between £305 and £335 per year.
For more information on potential savings for residents of Northern Ireland, see the Energy Saving Trust’s website.
Surplus Heat
Those in a heat network can make even more by providing their surplus heat to others. In total, homeowners can be paid up to 8.5p/kWh for the heat they generate and use.
To be eligible, a home or business needs to have an approved method of producing renewable heat installed on their property. Such products include domestic biomass boilers, which burn wood pellets, corn, or logs to generate heat instead of using fossil fuel.
Customers are finding that installing domestic biomass boilers is financially positive in two ways:
- Reducing the need for costly fuel.
- Earning a stipend from the Renewable Heat Incentive
It’s imperative to remember that biomass boilers are a quality entity, and the renewable heat incentive is only a minor reason for implementing the system in your home. Even if you were never to receive any payment from the RHI, boilers help you save money by cutting down on annual fuel costs per year.
Water heaters, furnaces, and other components that run on burning biomass are much healthier for the environment and are one of the major steps in making your property self-sustainable.
Are Biomass Boilers Expensive to Run?
To give you an idea of biomass boilers and their running costs, below are the price estimates for 2022 as compared to other energy sources:
| Fuel Type | Estimated Average Price Per Kilowatt Hour (kWh) in England, Wales, and Scotland | Estimated Average Price Per Kilowatt Hour (kWh) in Northern Ireland |
|---|---|---|
| Biomass Pellets | 6.0p | 4.97p |
| Electricity | 18.7p | 16.2p |
| Gas | 4.6p | 5.6p |
| LPG | 7.7p | 8.6p |
| Oil | 4.8p | 3.5p |
| Coal | 4.7p | 4.7p |
Please note this guide is for your information only. Prices obtained from the Energy Savings Trust in December 2021. Your actual costs may vary according to your choice of heating system, your usage, and your tariff.
In 2020 (the most recent year available at the time of posting), British households paid an average of £582 for their gas bill and as much as £705 for electricity.
Is a Biomass Boiler Right for Me?
It can be hard to decide whether or not a biomass boiler is right for you – especially when they carry such high installation and purchase fees, and can cause some disruption at home to get going. Here are the main advantages and disadvantages of the boilers for you to consider.
Advantages of Biomass Boilers
- Environmentally friendly, reducing the amount of carbon dioxide (CO2) that’s produced as a result of heating your home
- You can earn money from the Renewable Heat Incentive which gives you a fixed income for every kilowatt-hour of renewable heat you produce
- Appealing environmentally-friendly credentials for your home when you come to sell it on
Disadvantages of Biomass Boilers
- High initial costs for fitting and purchasing the biomass boiler
- Only possible for those who own their homes and can change their heating systems
- They won’t always save you money if you’re switching from a newly-fitted, A-rated boiler
- You’ll need a lot more space than you will for traditional heating systems
How Do I Find and Hire a Biomass Boiler Installer?
The best way to go is to seek recommendations from family, friends, and neighbours for word-of-mouth connections. If you know someone on your street who has had a biomass boiler installed recently, it’s a good idea to get in touch with them to ask if they’d recommend their installer to you.
If you’re not able to speak to anyone who has had a biomass boiler fitted recently, you can always search the HETAS register to find reputable installers in your area.
You can also use HouseholdQuotes to search for traders in your area, and by doing so, cut down your search time as you can keep your search consolidated to just one website, instead of having to switch between many different tabs.
Ensuring the Professional Is the Right Fit
First and foremost, as with any home renovation project, you must ask for a written quote. As a special note for this project, you should make sure that any biomass boiler you purchase qualifies for the Renewable Heat Incentive—be sure to check when you receive the quote.
When it comes to your installer, you should seek out their references from previous customers to get a feel for their past work. Alongside this, if your trader has any photographs or videos of their past jobs, it’s a good idea to take a look at them to see if you like what you see – this can be especially useful with storage, as there are different options when it comes to biomass boilers.
Your trader should be open about their insurance, but you should always double-check they have sufficient policies in place, and with that, you should check the manufacturer’s warranty on your chosen boiler to make sure that’s what you want.
Final Checklist
If the time has come to switch up your energy source and you think biomass boilers are the way forward, make sure you check off the following things on our conclusion to ensure you consider every angle during this project.
- Decide which type of biomass boiler is right for you – consider the different types of fuel, and their advantages and disadvantages
- Figure out your potential savings
- Make sure the boiler you choose is eligible for the Renewable Heat Incentive
- Make sure you have sufficient space for your fuel store, being airtight and secure
- Understand if you need to change anything inside your home – from radiators to installing a hot water cylinder if you don’t already have one
- Seek out recommendations from friends and family for traders, or use HouseholdQuotes to find your ideal trader with minimal fuss
- Take a look at second-hand biomass boilers to see if they’re an option for you
- Enjoy your new biomass boiler and environmentally-friendly heat source!
Frequently Asked Questions
How Do Biomass Boilers Work?
Do I Need Planning Permission for a Biomass Boiler?
What Size Biomass Boiler Do I Need?
To calculate output based on the size of your home, convert the size of your home into cubic metres, then divide by 30. (If your home is very well insulated, you can divide by 50 instead.) This will give you the boiler output you need in kW.
Do Biomass Boilers Work as Well as Gas Boilers?
How Long Do Biomass Boilers Last?
How Often Should I Service My Biomass Boiler?
What Can You Burn in a Biomass Boiler?
How Many Pellets Does a Biomass Boiler Use?
How Long Do Wood Pellets Last?
Ecowood Pellets says that wood pellets can last indefinitely if kept in good conditions, and they don’t get wet.