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Frequently Asked Questions

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Isn’t burning wood bad for the environment?

Carbon dioxide emissions from woodfuel systems are 95% lower than gas, oil, LPG or electric systems in most cases.  This is because the carbon dioxide that is released from burning wood was the same amount that was absorbed from the atmosphere during the growth of the trees.  The only new carbon dioxide released is from the fossil fuel used during its processing and transport.

Sulphur dioxide emissions from woodfuel boilers are also much lower than other fossil fuels and the emissions of other air pollutants such as small particles (PM10 and PM2.5) and nitrogen dioxide (NO2) are lower than coal, equivalent to oil and slightly higher than gas fired boilers.

Where can I buy woodfuel?

For national and regional woodfuel suppliers see Woodfuel suppliers in South east England

Why are wood-fuelled boilers more expensive?

The capital costs of wood-fuelled systems are higher than for oil or gas because the systems tend to be larger and involve a higher degree of engineering, due to the physical properties of wood, but the outlay can be recovered through lower fuel costs. The pay back time for the extra capital can be as little as three to five years. Wood chip fired heating systems of less than 500kW cost between £350-950 per output kW, but for systems over 500kW, capital costs fall to £350-450 per kW. This covers the core components; the boiler and handling system, flow and return systems and piping. Pellet systems tend to be cheaper. The capital costs of installation of a wood-fired heating system are variable and additional costs, such as a fuel reception facility and boiler house etc, may add to them. These figures should therefore be seen as a guide only. It is also worth noting in recognition of the potential of wood fuel to reduce carbon emissions, there are a number of schemes that will give grant support to help cover capital outlay on renewable energy sources, for more information see our Benefits and Grants page.

Where are the markets?

Schools, colleges, care homes, prisons and business parks are switching to wood fuelled heating. The South East has recently invested in some 70 industrial or commercial boilers (chip or pellet) and thousands of domestic log-fired stoves.

View Google Map of existing woodfuel installations in the South East

What returns can I expect?

  • Local woodlands provide low value fuel for heating. Many country estates have installed large-scale systems to save costs by generating heat from their own woods.
  • Clean wood by-products (e.g. from tree surgery or saw milling) can be readily sold into the woodfuel supply chain.
  • Woodfuel systems have lower lifetime (typically 20 years) costs than fossil fuel plants. They are generally cheaper to run than heating oil, LPG and electricity and produce lower carbon emissions.

How can woodfuel benefit wildlife and landscape conservation?

  • Cutting wood opens up woodlands for flowers, insects, birds and small mammals, including rare butterflies and threatened species such as dormice and nightingales.
  • Cherished woodlands are seldom ‘natural’ but have developed thanks to a long history of management. New woodfuel markets will secure the future of historic wooded landscapes such as the Weald and the Chilterns.

Woodfuel Quality – what do you mean?

  • Quality is critical. Clean wood with a low moisture content and consistent size is essential.
  • Woodfuel is generally graded and boilers are rated to accept a particular standard of fuel. Sub standard chips or pellets will block the boiler feed and its operation.
  • Suppliers must comply with boiler requirements and their specified production procedures.
  • For more information about woodfuel quality standards see the Biomass Energy Centre Standards Page 

What contract options are available?

  • Selling by the load/per m3, delivered to the end user.
  • Selling standing in the wood or cut at roadside to an intermediary.
  • Selling heat, an energy services contract (ESCo) where the supplier owns the boiler and the user only pays for the metered heat used.

Which type of woodfuel system should I install?

If you’re uncertain whether to go for chips, logs or pellets, space heating only or a hot water boiler, this decision tree diagram (pdf:245kb) may help.

How much woodland do I need to heat my building?

If you have a biomass boiler project in mind and you would like to estimate how much woodland might be required to provide fuel for it, this How much land spreadsheet.xls  might help. 

How many buildings could my woodland supply?

If you own an area of woodland in the South East and would like to estimate how many buildings of different types and sizes it might be able to supply, download this How many buidings spreadsheet.xls (386kb)

How do I convert between different pricing units?

If you are used to selling your wood in cubic metres of roundwood but you’re being asked for a price in cubic metres of chip or even in p/kWh how do you convert the price? This price conversion spreadsheet.xls (91kb) might help.

Where can I go for more advice?

The Biomass Energy Centre  is the Governments one-stop-shop for help and advice on biomass and woodfuel in the UK.