Do wood burning stoves harm the environment?
26th March 2018
Do woodburning stoves harm the environment?.
In the press lately there has been some discussion about the effect of woodburning stoves and the emission of PM2.5’s into the environment. We know that these are a major cause for concern in city centres due to the huge pollution problems caused by diesel engines. Of course this is a major health issue due to the increased risk of disease and stroke that these particles are thought to be responsible for. As a manufacturer of woodburning stoves we are well aware that this can be an issue and the industry has been busy working on this for many years.
What are PM2.5 emissions?
PM2.5 refers to atmospheric particulate matter (PM) that have a diameter less than 2.5 micrometers, which is about 3% the diameter of a human hair. Commonly written as PM2.5, particles in this category are so small that they can only be detected with an electron microscope. These are created by combustion and released into the atmosphere by means of a chimney or exhaust. There have been estimated that in winter period the PM2.5 levels are increased by burning of wood in stoves and this is a cause for concern.
What is the stove industry doing to reduce PM.5 emissions?
Woodburning stove manufacturers including Vesta Stoves have been working for many years through design and material selection to increase the efficiency of woodburning stoves and therefore reducing the emission of PM2.5 particles. Through modern techniques and design of triple combustion zone appliances we have bbeen able to maximise the burned materials in the stove and ensure that our effect on the environment remains a positive one.
Whats the answer to reducing the PM2.5 emissions from wood burning stoves
Hetas are heavily involved in targeting the fuel suppliers in the UK and are introducing a scheme to certify wood fuel as ready to burn. This means that woodfuel marked with the logo can be certified as having the correct moisture content to burn in your appliance. Hetas recogniser that the issue is not with high efficiency wood stoves but the fuel that is chosen to be burned with in them. The burning of wet or low quality fuel may well be lower cost but is also responsible for causing the PM2.5 particles emitted from wood stoves.
Below is a table containing the recommended seasoning times for different fuels that should be adhered to for controlling emissions. Source: https://solidfuel.co.uk/wood-burning-guide/
| Weight per m3 in kg |
Gross heat value kW/kg (btu/lb) |
% Moisture when green |
Seasoning time in summers |
||
| Hardwoods (fully air dried) |
Ash | 674 | 4.1 (6,350) |
35 | 1 |
| Beech | 690 | 4.3 (6,700) |
45 | 1-2 | |
| Birch | 662 | 4.1 (6,350) |
45 | 1 | |
| Elm | 540 | 3.6 (5,600) |
60 | 2-3 | |
| Oak | 770 | 4.5 (7,000) |
50 | 2-3 | |
| Poplar | 465 | 2.6 (4,100) |
65 | 1 | |
| Softwoods | Pine/Fir |
410 | 2.6 (4,100) |
60 | 1 |
In conclusion the pm2.5 particle issue although heavily increased by diesel engines can be influenced by burning unseasoned fuel or fuel of a low quality. We are working to educate the user on what to burn and most of all select a fuel supplier that is recognised by a scheme such as ready to burn.Above all Vesta Stoves will continue to work on efficiency improvements and continue to lead the way in stove innovation in the UK
