Installing a biomass boiler

Last updated Wednesday 2 July 2008

Let nature get you all fired up

If your boiler is on its last legs, replacing it with a wood-fuelled system could win you some serious greenie points.

With biomass central heating, a wood-burning stove and a boiler provide all your heating and hot water, reducing your CO2emissions by up to 90%. It's not cheap to switch, requiring major refurbishment but, once installed, you'll at least be immune from big hikes in gas and oil prices.

You'll need plenty of space to store the fuel and, ideally, a local fuel supplier.

Read more below
Photo: Installing a biomass boiler

Saves from 3,100kg to 8,000kg of CO2 a year

149 Bloomers are doing this

CO2 reduction 5 out of 5

Cheapness 3 out of 5

Popularity 3 out of 5

Cost 4,000 - 12,000

About these ratings

In this article:

What is it?

Pub Fact

  • 47% of Scotland, 40% of England and 10% of Wales is covered in woodland
  • Although forests are shrinking globally, Europe's forests are growing by 3,500 square miles every year. That's almost 100 football pitches every hour
  • A cubic metre of wood stores roughly 0.8 tonnes CO2
  • As trees grow they naturally absorb CO2 from the atmosphere

Biomass refers not just to wood but to fuel derived from any living or recently dead organic material - plant matter or even cow dung. It does not include fossil fuels, which have formed - and stored their carbon - over millions of years.

Because the CO2 released from biomass is balanced by the CO2 absorbed during its production - and because new plant matter is re-growing all the time - it's regarded as 'carbon neutral'.

Back to top

How will it make a difference?

  • Depending on the size of your house, sourcing all your heating and hot water needs from biomass could save between 3,100 and 8,000kg of CO2 a year
  • If you find a local, cheap sourclone of wood it could save around 200 a year on fuel bills, but if not, you could pay around 8 more than the average gas bill each month. The upfront costs are also considerable

Grants of up to 1,500 are available, from the Low Carbon Buildings Programme, but to qualify you need to have insulated your loft, fitted cavity wall insulation, use low energy light bulbs and added controls for your heating system. But a stove and boiler can still cost up to 8,000, and up to 2,500 for the installation. The Energy Saving Trust estimates an extra cost of 2,000 over the life of the boiler if switching from gas to biomass.

Back to top

What's the debate?

In many developing countries where wood is the main source of fuel, forest resources are now scarce or dwindling. Controversial new research even links wood burning stoves in developing countries to increasing climate change.

Wood is regarded as a sustainable fuel source in Britain, however, because the forestry industry currently plants more trees than it chops down, and our coniferous plantations are replenished much more quickly than tropical forestation.

Back to top

How do I do it?

  • Decide whether to switch fully to biomass central heating or just to top up your existing heating with a wood burning stove
  • Pick your system - not all of them will meet your particular heating needs, so get the advice of a good heating engineer and make sure your installer is approved by HETAS
  • Search for a boiler supplier via the Log Pile website and check that the boiler complies with the Clean Air Act
  • Make sure your installation complies with safety and building regulations (see part J of the report)
  • If you have a chimney, make sure it's lined and have it swept at least once a year
  • Find a fuel supplier with BigBarn and purchase seasoned wood by volume rather than weight, as much of it is water
  • You can use any wood, as long as it's not painted or treated, but buy British wood from sustainable sources and not tropical hard wood

Back to top

What's stopping me?

"I don't have a chimney!"

Not a problem. When your stove and boiler are put in, you will just need to have a flue (a vent) installed through your outside wall.

"I don't see myself as the axe-wielding type"

You don't need to be. You can buy pellets or logs ready-chopped to the desired size.

Back to top


If you like this action send it to a friend

Share this

Back to top


Baz, Shrewsbury 2009-01-16

In our self build home we have a 16kW wood burner with a wrap around boiler. The boiler puts 13kW into the central heating
A gas combi boiler is installed upstream from the wood burner (WB). If the WB is heating the water sufficiently, the gas boiler won't come on. In the morning the gas boiler heats the house until I light the WB and should the WB go out, the gas takes over so we are never cold. The water is circulated by a pump next to the WB controlled by a cylinder stat strapped to the back of the WB, so it's all automatic. A bypass was fitted to the combi gas boiler to allow water to circulate in the system when the combi was off, you can't push water through the combi because of its internal diverter valve. The bypass is just a 22mm non return valve connecting flow and return before the boiler, with the spring taken out and mounted so that gravity closes the valve. Busybee, this is our first winter, I don't know what the gas bill will be yet, but I expect it to be smallish.

busybee, Nottingham 2009-01-10

This is the second winter we have had our wood burning stove installed which is linked into our gas central heating system. We were able to reduce our monthly gas payments to £5 last year and the gas company have not asked for an increase this year dispite the price hikes

Flower representing the 'Installing a biomass boiler' action

People using this site

2% of Bloomers are doing this action

3% of women in their 60s are doing this action.

Top 3 popular actions that females aged 60-69 are doing

More about actions by people of this age and gender.

Latest actions on Bloom

Latest related BBC News stories

RSS icon | News feeds | View all stories

Related links

Elsewhere on the web

Related links open in a new window. The BBC is not responsible for content on external sites.

Browse all actions

Glossary terms used on this page
Biomass is renewable organic matter that can be used as fuel. It is living or recently dead material - wood and other plant matter, or even animal waste. Fuel derived from biomass is known as biofuel. It does not include fossil fuels, which have formed - and stored their carbon - over millions of years. Because the CO2 released when biomass is burned is balanced by the CO2 absorbed during its production - and because new plant matter is re-growing and absorbing more CO2 all the time - it's regarded as carbon neutral.
CO2, or carbon dioxide, is made up of the elements carbon and oxygen. It exists quite naturally in our atmosphere, as part of the carbon cycle. Everyday processes in the plant and animal world both add CO2 to the atmosphere and take it out. However, because it is a greenhouse gas - meaning it affects the temperature of the earth - the exact level of CO2 is important. Burning fossil fuels releases CO2 into the atmosphere, hence the anxiety that extensive use of these fuels is causing climate change.
Carbon is the fourth most common chemical element in the universe, and carbon compounds - in other words, carbon chemically combined with other elements - are the basis of all known life forms on earth. Pure carbon appears in many apparently diverse forms, from diamond to graphite to charcoal, but it is much more commonly found in substances such as coal, oil, natural gas, wood and peat that we use for fuel. When we burn these substances to provide energy - either directly in our homes as heat, or in power stations to produce electricity - the combustion process produces 'oxides' of carbon, including the gas CO2.
Carbon neutral
A business or a process is described as carbon neutral if it doesn't add to the net amount of CO2 in the atmosphere. This can be achieved either by emitting no CO2 to begin with - by using only renewable energy, say - or by 'offsetting' emissions (a controversial issue) which means compensating for emissions by another action which might reduce atmospheric CO2, such as planting trees. In practice, it is impossible for a person to live in an entirely carbon neutral way because even if you cut out energy consumption derived from fossil fuels, most products and services people rely on will have embodied emissions.
Climate change
Climate change is the variation in the average global or regional climate as measured by yardsticks such as average temperature and rainfall. This variation is caused by both natural processes and human activity. Weather is what happens over days or even hours, whereas climate is the average weather measured over a longer period. Increasingly when people refer to climate change, however, they specifically mean the phenomenon of global warming.
Emissions are the CO2 (and other greenhouse gases) produced by energy use, usually calculated and stated as an annual tally: also referred to as your carbon footprint. Your personal emissions can be direct - such as the gas you personally use to heat your home or the petrol you burn to power your car - or indirect - meaning the energy use that has gone into the products or services you buy. The latter, such as the emissions caused by the manufacture of your new TV, or the packaging your food comes in, are also referred to as embodied emissions.
Fossil fuels
Fossil fuels are the deposits of crude oil, natural gas and coal formed by the decay, over millions of years, of organic material (plants, trees animals and bacteria). Because the combustion of fossil fuels releases carbon that has been out of the natural carbon cycle for so long (unlike with living or more recently dead organic matter, known as biomass) it affects the balance between stored carbon and carbon present in the atmosphere as CO2, a greenhouse gas.
Sustainability - whether applied to energy, technology, industry, agriculture or just consumption of resources in general - refers to the concept of using things at a rate that, while meeting our own needs, does not compromise future generations' ability to meet theirs. In environmental terms, a process or industry is unsustainable when it requires natural resources to be used up faster than they can be replenished. navigation


The BBC is not responsible for the content of external sites. Read more.

This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.