Stove Industry Alliance responds to wood-burning stove and HGV comparison
In a recent article, Air Quality News reported that Eco-design wood-burning stoves emit 300 times as much particulate matter (PM2.5) as the most modern HGV, the Stove Industry Alliance has responded to this comparison.
The source of the original HGV figure is a report by the European Environmental Bureau called ‘Where there’s fire, there’s smoke.’
This report looks at the amount of PM2.5 emissions given off by generating a GJ of heat in a stove compared to the amount generated by creating a GJ of power in an HGV.
The resulting claims are based on simplistic calculations using permitted rates of emission and do not consider either real-world use or non-exhaust emissions.
Furthermore, these permitted emissions rates rely on vastly differing measurement protocols and techniques. It should also be noted that there are several unreferenced assumptions, and the report does not appear to have been independently peer-reviewed.
James Verlaque, technical manager of the Stove Industry Alliance, commented: ‘We must be very careful comparing two completely dissimilar things, and this particular comparison is highly misleading – like comparing apples to oranges. Comparing the emission rates between sources only tells part of the story. It is important to look at the impact of real-world use, and that paints a very different picture.’
According to Defra’s 2020 report, Burning in UK Homes & Gardens, by Kantar, on average, stove users light their appliance for 29 hours a week (between 3.7 and 4.5 hours a day) during the winter.
Under current driver’s hours rules, an HGV can be driven by the same driver for 9 hours a day. This is a much longer daily run time and is not subject to the seasonality of wood-burning stove use – HGVs operate 24/7 up to 365 days a year. Over the course of a week of typical use an Ecodesign stove will emit 20.16g of PM2.5, whereas a Euro 6 HGV will emit 271g of PM2.5. That’s over 13 times the amount of the stove. Using HGVs as a comparison is therefore deeply flawed.
It should also be noted that emissions from wood-burning stoves are typically at 5 metres plus above the ground, whereas HGVs emit at near ground level. There is wide agreement in the scientific press that non-exhaust emissions of particulate matter from vehicles are greater than exhaust emissions, with AQEG estimating that this could be as much as double the emission rate from the exhaust.
Andy Hill, chair of the Stove Industry Alliance, added: ‘In order to tackle poor air quality we must be sure to fully understand the impact of all sources of emissions and not be selective. It’s simply not helpful, and is indeed misleading, to point the finger at one source or partial emissions from one source, without looking at all sources with the same degree of focus. In the case of the comparison presented by the EEB, no consideration has been given as to how stoves and HGVs are used in real life or the height at which they vent. Neither have the non-exhaust emissions of the HGV been factored into the comparison. This further analysis clearly shows that the 1:750 claim is misleading and fundamentally flawed by failing to take account of the real-world use of wood-burning stoves compared to HGVs.’
The Stove Industry Alliance claim wood burning stoves are not an environmental problem because they are not used much compared to HGVs. If that is true, then the Flying Scotsman must be the greenist form of transport.
The SIA “Stove Industry Alliance responds to wood-burning stove and HGV comparison” article is lacks balance rebuttal of unsubstantiated claims is irresponsible journalism.
The SIA are frequently active on social media and other publications and will lobby Government and media quite heavily to protect their interests and have even commissioned their own report to make these unsubstantiated or peer reviewed reports (at their cost, not independent).
This is a serious attempt by the stove industry to challenge the Government’s own data for PM2.5 regarding the contribution that comes from wood and solid fuel burning. The approach is a smoke screen which tries to muddy the water with spurious claims about bonfires, barbecues and fire pits, which are undoubtedly a serious nuisance but this by its nature will usually only be for short periods mostly in daylight and unlike burning solid fuel in the home do not go on for 9 months or more of the year for many hours at time on a majority of days, and their denial of the high (comparative to other sources) pollution from stoves is of concern as the data they seem get publicity using is often unsupported by independent peer review and their publicity is more economical with the facts making limited comparisons to other far less polluting sources such as gas or air source heat pumps (running on renewable energy).
Speaking as someone with many years personal experience of living near several homes within 250 m (and one with a chimney closer than 2 m from my home) with some form of Eco-design stove installed, I have investigated the subject thoroughly but would not really need any further understanding or research as to where the pollution comes from, and that down drafts and temperature inversions in cold weather trap the pollution at ground level making emission height irrelevant. If emission height were a factor then why does everywhere across the country stink of wood smoke at ground level during the heating season which comes from these same chimneys because down drafts and normal turbulence experienced around buildings along with temperature inversions will bring the pollution down to ground level.
The pollution comparison with HGV’s the SIA tried to exclude was an example of how much worse the pollution from a solid fuel fire is and justifiable comparison. Whilst living in a quiet residential area I don’t usually find 18 HGVs parked outside my home for 9 hours at a time as they obviously spend most of their time on Motorways, Dual Carriageways and A Roads away from residential areas and if they did I’m sure the Council would stop it, unfortunately my personal experience over 5 years is that Councils are unwilling to do anything to stop residential wood stove pollution.
Previous challenges to the SIA regarding comparisons with HGV’s are actually not unfair as they are heavily regulated, emission controlled, subject to regular MOT’s and spot checks (as are all transport ICE vehicles) whilst solid fuel stoves are a static device installed where their emissions based on flawed (recently published US and Australian studies) where lab based checks were shown as flawed. Also, once installed stoves are mostly unregulated or independently controlled with the person operating them effectively free to use whatever fuel they choose, and they can even adjust the amount of air (throttled or chocked) passing over the fuel which changes/increases the amount of pollution produced making pollution worse. Stoves, when lit, emit 100% of their emissions on to close neighbours and are much more of a problem to those close neighbours as they do not move away and also produce far more pollution than all traffic almost regardless of how dry the fuel is or the fuel that’s used.
I like the way you stick to your guns without reading the aritcle or taking on board most of what it actually said.
I fully endorse Chris’s comments about the suffering wood stoves cause. The smoke is often pushed to the ground by a cold inversion as Olaf says. Meanwhile at the EP UK conference Johan Kuyliensterna told us that black carbon is 460-1,500 times more globally warming than CO2 per unit mass. Climate change is also bad for your health even if it is only getting too hot in summer, especially if it causes catastrophic events. If someone drives down the road near their child at dangerous speed the wood burning people would probably report it to the police. If they cause dangerous asthma to someone else’s child they think its nothing and the sanctions against it are virtually non existent
Liz.
It is interesting watching this kind of debate playing out in the UK, after all the research and information available on solid fuel heaters, which points to their effects on humans. Perhaps this type of comparison has it limitations, but much of the response to the report looks like obfuscation of the kind that has been pushed in various countries over some decades – some might even say “smoke and mirrors”. I note with interest the criticism that the height at which wood heaters vent needs to be taken into account.
This is quite mis-leading. It is well-understood by air quality practitioners and regulators, that mixing of air in urban areas is typically pretty-well complete within the sorts of heights under discussion, so it is not unreasonable to make comparisons of various emissions into this layer.
Further, there are really two separate (but inter-related) effects of smoke from domestic solid-fuel heaters.
One is the contribution of each source to the overall air quality of an area, and depending on the topography, even a few heaters can impact air quality at considerable distances downstream – for example, through patterns of drainage down a valley.
The other effect, alluded to in some of the feedback on this page, is the direct impact of emissions on near neighbors. Apart from clear health implications, this can be extremely irritating, and impact the lifestyle of those who live with the issue. This can be be of especial concern where emissions become caught in the downwash from air flows across the roofs of houses, which can deliver fresh emissions directly through windows or other ventilation access points into the interior of a dwelling.
Thanks. Youre right and it goes well beyond irritating if you and your family have permanent coughs and sore throats because of the neighbours smoke but can do nothing about it. If they were leaving their engines running outside your front door for hours, you would be justified in complaining and most decent neighbours would stop I hope. But these wood burners are very different. They don’t get it. A few are considerate but many are not. they still think the wood smoke is harmless and they like it themselves and they see it as their right to burn what they want when they want. they think the air somehow cleans it up.
Kocbach, A., Li, Y., Yttri, K.E. et al. Physicochemical characterisation of combustion particles from vehicle exhaust and residential wood smoke. Part Fibre Toxicol 3, 1 (2006). https://doi.org/10.1186/1743-8977-3-1 ‘The total PAH content was higher for combustion particles from wood smoke as compared to vehicle exhaust, whereas no source difference was found for the ratio of organic to total carbon’ ‘A higher mutagenic and carcinogenic potential of the wood smoke particles seems likely, however, in the light of the similar PAH profile but larger PAH content compared to vehicle exhaust.’
Interesting that the report was published in 2020, presumeably over the winter 2019-2020. What are the figures for lockdown,when more people were working from home? I have several neighbours who light a woodburner 16 hours daily, more at weekends. And what are the figures since the rise in fuel prices? Proper wood burning fuel is not cheap ; the local (public designated nature park) woods are being stripped by chainsaws and the wood sold freely on e-sites. I have even filmed this happening, but my local authority refuse to view the film saying they must witness it themselves, so no action is taken. Really ? And it’s getting worse by the week.
Although living in a designated Smoke Control Area, there is no enforcement. You can fill in an online form or contact the main switchboard. It takes 48 hours to process a report.Pointless; “we have to witness the incident ourselves to take action” is the standard response. And they refuse to look at any film/photographic evidence.
Well, all of that is neither here nor there if your neighbours are pumping out vile wood smoke over you day and night. You don’t give a monkey’s about now many HGVs (also bad, I know). you just want the smoke to stop so that you, and your children, can breathe and not cough all night and have a sore chest in the morning and have to go back to the doctor for asthma inhalers. All wood stoves emit air pollution.They are all unhealthy. Some make less smoke than others which is better but even when the smoke it not obvious you can smell it and it irritates. At least you can ask you neighbour not to leave his HGV engine running ouside your house for hours if that is the case but most wood burners would not take kindly to your request.Because to them the smoke is just fine and they are probably cigarette smokers anyway and can’t smell or tatse anything anymore. The fact the smoke might be damaging their health too doesn’t seem to trouble them. OK, that’s up to them but why should they make others ill and get away with it? Forget the trucks.
If you live near a newly installed Ecodesign or Clear Skies Mark stove, you don’t need any further understanding or research as to where the pollution comes from, and that down drafts and temperature inversions in cold weather trap the pollution at ground level making emission height irrelevant.
If emission height were a factor then why does everywhere across the country stink of wood smoke now at ground level – see down drafts caused by turbulence around buildings and temperature inversions.
HGVs are mobile spending most of there time on Motorways, Dual Carriageways and A Roads away from residential areas, whereas stoves are static emitting 100% of their emissions on to close neighbours. For once the SIA have got something right – the comparison to HGVs is unfair… on HGVs. Stoves are far more of a problem to close neighbours being static.
You can get to proper relevant research work from here – https://www.theguardian.com/environment/2021/dec/17/wood-burners-urban-air-pollution-cancer-risk-study
Well done on correcting this stupid comparison which is endlessly touted in articles without any quantifiable measures. Burning wood is necessary for a portion of the U.K. who rely on Oil for heating, or is oil better for the environment? Not everyone lives in polluted urban streets or has neighbours close enough to worry them, it’s called the countryside, have a look next time you are passing through in your cars….
I can tell you 100% than living next door to a heavy wood stove user in a rural area is just as awful as one in a town. Burning wood as somone’s only source of heat is rare these days. You can still have an LPG gas tank for heating and cooking if you live out of the way and are not on mains gas. I agree oil ch is not good for the environment or lungs but nor is wood smoke. I agree that this comparison needs to stop now. The SIA have said their bit and ought to leave it at that. Truck exhaust and wood smoke are both unhealthy. the science says so and we know from what it does to our lungs.
You forget Chris that LPG and oil are Fossil fuels. Regardless of the emissions they themselves create, they have taken millions of years to manufacture, then there is the pollutions emitted when dredging it up from deep underground, and the transport. The carbon footprint is huge. Locally sourced wood is still massively sustainable, and when seasoned properly, the harmful emissions are very limited (less than cooking a roast dinner! I know, I have done the tests)
I know the LPG is a fossil fuel and that we want to move away from that, of course. I was talking only about unhealthy fine particle pollution. The CO2 problem and the PM2.5 etc. are not the same thing.Locally sourced wood can be said to be sustainable, I agree. But that’s only if the trees are being replaced and that is not always the case. You say the emissions can be very limited and I’m sure you are right but not eveyrone is as conscinetious as yourself Mac. That is a big part of the problem – bad burning by irresponsible people. You may have tested the emissions and yes cooking particles can be far worse I’ve read, and from a toaster, but I still maintain that living next door to someone who puts out brown smoke almsot day and night, and the local authority doesn’t want to know, is dire. Our old LPG never made us ill but all that wood smoke certainly did.
The problem is not just bad burning by irresponsible people. It’s dire living near someone who has a Defra approved stove and is burning all day and night with no visible smoke a lot of the time, because you can always smell it and if you can smell it, you are inhaling pollution. My neighbours have a wood burner because they think it looks nice, but since they got it my health has been really bad. I’ve been unable to leave the house for weeks because the air outside my house is so polluted by my neighbour’s Defra approved stove and smokeless fuel.
I dont quite understand why you say homes with Oil CH also need wood burning stoves?
I live in NI where many homes like mine use oil-fired boilers for their heating and hot water. There is no need for wood stoves too. For those that do have them it’s typically for aesthetic reasons rather than an actual need to heat their homes on top of their Oil CH.
Whilst I dont find the comparison between emissions from wood stoves and HGVs particularly useful, I suppose it’s because when discussing air pollution road traffic always seems to be the main focus. The point is being made that wood burning stoves, particularly if their use increases due to the attempt to stop using gas and oil for central heating, are very polluting particularly in the case of particulate matter which scientists now agree has long-term health implications for humans.
i live in the countryside and ALL my neighbours burn wood, even pallets, It is probably a lot worse than you could imagine
What we burn we breathe!
We should stop burning anything unecessarily.
True but we also have to be realistic. Currently gas, oil and to a much smaller extent wood are required for heating homes.
The government needs to offer more assistance to convert to green systems rather than a paltry £5000 to a limited number of homes in England, when the typical costs to install an air source heat pump seem to range from £8,000 to £12,000. And there seems to be evidence that such heating systems are not always good at heating the home!
What evidence? If a house is well insulated, I don’t see why an air source heat pump can’t do the job. They will improve in time too and prices will come down but you;re right our government needs to provide more help for those needing to make the change.
I agree comparisons to HGV a grossly unfair. For starters the vast majority of HGV emissions are away from residential areas – on motorways, dual carriageways, A-Roads, B-Roads etc. You will very rarely see an HGV in a residential area. Whereas 100% of stove emissions are where people live, children play and sleep. Therefore if you analyse WHERE the emissions are emitted, stoves are actually even worse than first thought when compared to HGVs.
Secondly, it would be better to compare like for like – domestic heating. An electric heat pump is zero emission therefore a stove is infinitely worse. According DEFRA an Ecodesign stove in perfect operating conditions which the average user is unable to replicate in the real world emits 265 times the PM. Real world conditions when taking into account start up, burnout and pretty much everything in between optimum operating conditions are actually far worse.
The SIA never publishes figures comparing a stove to a gas boiler. I can’t imagine why.
The SIA never publishes data that quantifies where the emissions are emitted when publishing their nonsense vs HGVs. I can’t imagine why.
Thank you. Well said. The SIA jsut want to sell more stoves which will pollute the air even more. Selfish.
The SIA reports, although commissioned by the SIA are carried out independently. Additionally heatpumps are full of plastic (petroleum derived material) and refrigerant gas, and incredibly harmful greenhouse gas. Additionally their average lifespan is 7 years, that’s a quarter of the life span of a wood burner. Non of you are looking at the bigger picture here
Although an electric heat pump may have zero emissions, the substantial amount of electricity it needs to operate may not come from renewable sources, so that has to be taken into account when calculating emissions.
What we burn we breathe. It’s that simple!
The rise in popularity of wood-burners and promotion of burning in general is extremely dangerous (remember diesel?) & damaging to health and the environment. All burning is polluting and unsustainable in practice (given the length of time it takes to grow a tree and absorb the carbon burnt). Trees need to stay growing to tackle the excess carbon in the atmosphere.
Yes. It was the same with cigarettes years ago. They were supposed to be good for us! We should be planting trees and letting them grow until they decay naturally,not burning them.
I agree that we should not be comparing different sources of pollution. What we should be comparing PM2.5 pollution from wood burning stoves with, is if people did not install these largely unnecessary forms of pollution. Just think how much cleaner our air would be and neighbours would not have to suffer ill health that results from living near a wood burner.
I don’t understand your justification that emissions from wood-burning stoves are typically at 5 meters plus from the ground. I’m only 5ft tall and the emissions from my neighbour’s chimney definitely drop down to my level.
Exactly. If you watch chimney smoke it does descend. It also drifts over the whole street before falling. The particles do not somehow disappear. Worst of all is that you cannot get away from it if the smoke comes from next door. You can at least step well away from vehicle exhaust if it’s coming from an idling engine and the latest HGVs are supposed to make far less pollution than previously. This is not a good compariosn anymore. We should be looking at the wood stove emisisons compared to other forms of heating not vehicles.I know gas is frownded on now because of the CO2 but wood burning also emits CO2. Gas gives off hardly any fine particles at all.
Well said , my high street is a place to avoid , there are no less than 50% of the few houses in the street ,burning wood, its like a fog, and of course, the owners are indoors