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    I've never quite understood the fascination with putting wood burning stoves in modern houses. It's one thing when the house is in a rural area and has its own supply of wood but they regularly feature in city self builds and 'grand designs'.

    I gather they're considered 'carbon neutral' - ie you're not burning fossil fuel - but is this, like Diesel cars, a mis-step? (Genuine question - i've not looked into this in detail.)

    • CommentAuthorcjard
    • CommentTimeJan 25th 2017
    Fossil fuels are carbon neutral if you can wait around a few aeons for them to replenish! Wood is really only regarded as renewable because it can be regrown in a human lifetime, but still, all you're looking at is "recycling on the macro scale". Eventually all those landfills will end up in the magma..

    And then, consider that nothing is renewable, really, because it's powered by the sun and that's got a finite burn life.. we're just measuring it relative to our blink of history, with a dollop of social conscience regards making our children wallow around in the mire we created..

    The fascination with wood burning stoves is pure traditionalism. We huntd and cavedwelled for hundreds of thousands of years but only farmed for a few tens of thousands. Burning things is intrinsic
    • CommentAuthortony
    • CommentTimeJan 25th 2017
    In cities and towns it is antisocial, highly polluting and down right dangerous to health to burn wood.

    And this is also true in houses, if you can smell it then it is doing you harm.
    I'd welcome your further comments, Simon and others.

    Pollution monitoring is not my speciailist area, though dodgy stats in the media are a little more so.

    From here that link looks like very dodgy reporting.

    For the 12% claim we have:

    "In 2009 coal and wood burning in the home was thought to be responsible for 12% of UK PM10 emissions [source - National Atmospheric Emissions Inventory], whilst research by King's College London suggests around 12% of the PM10 in London's air during winter 2010 arose from wood burning."

    ie an average measurement from a wide area over a long period.

    For the 50% claim we have:

    "This is not to underestimate the contribution of traffic emissions but wood burning, according to the experts, was making up half of the pollution readings at some monitors at some sites - all exacerbated by low winds not blowing away pollutants."

    which is *some* monitors at *some* sites ie a selection of peaks.

    And the BBC making a direct and dramatic comparison:

    "That is quite a leap from 12% to 50% in the levels of wood burning on Monday."

    To me the 12% looks like a wide average and the 50% a handful of spikes as I say.

    I expect the spikes were also there in the earlier figures, and average out to the overall "London" 12% number, and that the comparison is not valid in those terms.

    Or am I misreading this?


    As long as one dosnt eat well done/burned toast, or crispy roast potatoes, or smoke, or drink or fornicate, or sunbathe, or enjoy onesself, or drive or even breath etc etc.

    One should live forever.

    If all the published research data is to be believed.

    Whatever year mankind reaches the stars, or rather a human friendly planet, they had better keep their space suits on, simply because they will be so doncy bred anything other than absolutly "pure" air will kill them.

    What kind of world do people expect, while they keep breeding and overcrowding the finate resources of the planet, but want everything "perfick", for them.

    Rant over, & back to stoking up the woodburner.
    • CommentTimeJan 25th 2017 edited
    Posted By: orangemannotOne should live forever.

    One of the best places to live is in prison, very very few people die in one.
    But that is just playing with geo-statistics.
    The same is true of comparing diesel emissions with wood burning emissions, there are two parts to it:
    Emissions per kWh delivered
    Total Emissions

    Where Emissions are whatever combustion or environmentally damaging substance you wish to measure.

    So it is no good comparing say the reduction of natural resources i.e. diesel cars using less crude than gasoline cars, with PM10 and PM 2.5 particulates from wood burners.
    Where it gets difficult is comparing the utility value of each energy source. For some people, driving is an economic necessity that cannot be got rid of.
    Heating is a necessity for most people, and again cannot be got rid of.
    So it comes down to the best (generally the cheapest) way to reduce emissions from each class of energy usage.
    It would be pointless to spend £10,000 reducing household emissions by say 1 tonne, when for the same money you could reduce transport emissions by double (just made those figures up as a 'for instance').

    I still fail to understand the argument that it is alright to burn timber in a low populations area. It is not acceptable to dump asbestos is a low population area, or kill a cat, or stop education of young people, so why should it be acceptable to allow a heating system to pollute the environment.
    • CommentAuthortony
    • CommentTimeJan 25th 2017
    • CommentAuthorDarylP
    • CommentTimeJan 25th 2017
    @Simon Still,
    they (WBSs) can be used as 'lever' for Part L compliance, to squeeze over the line...:devil:
    • CommentTimeJan 25th 2017 edited
    Posted By: cjardWood is really only regarded as renewable because it can be regrown in a human lifetime
    Wood burnt as fuel doesn't renew itself anything like fully, unless ... (I'll come back to that).

    The classic proposition, to support carbon-neutrality of burning wood, is that
    'All the CO2 released by burning wood (or composting, eating or letting it rot) has previously been precisely absorbed by the growing of the tree, or looking at it another way, will be precisely reabsorbed by the tree that replaces it".

    But that ignores the other, major CO2 that's released, in addition to that by burning, by the whole process of forestry - planting, managing, harvesting, processing, distribution.
    All these are heavy on diesel (and in the old days on food for horses and foresters).
    And modern machinery chaws up the forest floor, which is an equal, if not greater accumulating sequesterer of unoxidised carbon, which gets released (that is far less with old horse forestry).

    Any claim that burning wood is carbon neutral must depend on the rate at which the forest floor also sequesters unoxidised carbon, in addition to tree re-growth.

    This must total-up to exceed
    not only the chawing losses mentioned above (which it maybe does equal or exceed)
    but also the diesel losses (which it doesn't, by a long chalk, by present methods).

    Comments on the logic of this - welcome.
    • CommentAuthorEd Davies
    • CommentTimeJan 25th 2017
    Carry fallen wood from the local woods or coppice your own trees with a solar-powered chainsaw and you're pretty sustainable from a CO₂ perspective. Use commercially grown wood trucked from the other end of the country or across the Atlantic and you're less so - some numbers are needed to say how much by.

    By sustainable I mean doing something which could be sustained for a very long time. There's an initial hit of transferring a small amount of carbon into the atmosphere but after that it'd be steady state in much the same way that animals eating vegetation has been going on for a while on this planet (~0.5 Gy) without causing a long-term trend in the composition of the atmosphere.
    The majority of wood for wood burners in my area are by-products of tree surgeons work. I suspect this is the case for many rural areas - wood doesn't come from forests grown specifically for the purpose but are a by-product of other work. Personally my wood comes from fallen trees from the farm next door, so minimal transport miles, although the COC2 impact depends on whether the trees are replaced.
    • CommentTimeJan 25th 2017
    So if it takes say 20 years to grow a small size tree that may give you 50 kg of dry mass suitable for burning, does burning it in one week still count as sustainable? Are you allowed to burn anything else before a new tree has been regrown.
    Or do you rely on a tree somewhere else putting on 50 kg of dry mass in that same week?

    Some of you may know that I have been running a tree growing experiment for the last few years, and I am still measuring in grams and centimetres, not kilograms and metres.
    • CommentAuthorEd Davies
    • CommentTimeJan 26th 2017
    Posted By: SteamyTeaOr do you rely on a tree somewhere else putting on 50 kg of dry mass in that same week?
    Basically, yes. As we have with food for the last 400 million years (on land, longer in the ocean). How many woodburners can be carried sustainably is a different question which I doubt simplistic experiments can answer usefully.
    • CommentTimeJan 26th 2017
    Posted By: Ed DaviesHow many woodburners can be carried sustainably is a different question which I doubt simplistic experiments can answer usefully.
    We can can answer that and it has been, by Prof Brian Cox for one. I think it was about 400 days to deplete the reserves at our current energy usage.
    I must admit that before I joined this site and saw the various threads about smoke nuisance, I believed the party line about wood burners being 'good for the environment, carbon neutral, a natural fuel source', etc, etc. I now know better.

    We have two wood burners that were in the house when we bought it and we intend to remove both as soon as we can. We're slowly improving the thermal envelope of the building with high spec double glazing, IWI, warm roof, improved air tightness and a MHRV system. I'm hopeful that these improvements will drastically reduce our heat demand and so the gas stoves we replace the wood burners with will hardly be used, except perhaps during cold snaps in summer and the shoulder months when it's more energy efficient to use them to take the chill off, than run the full central heating.

    As an aside, I have to say that I'm surprised with the comments from orangemannot, as they had the same tone as those coming from Prez. Trump and the other climate change deniers, something I didn't expect to read in here (Apologies if s/he was being ironic and I missed it!!)
    • CommentAuthorEd Davies
    • CommentTimeJan 26th 2017
    What does that mean?

    Does it mean, as I'm guessing, that if we (the human race) tried to get all our current energy use from burning trees then we'd run out of trees on the planet in 400 days? If so, it's a completely useless statistic.

    (Just to be absolutely clear: I think burning trees is a really bad idea but mostly for the particulate reasons. I don't see why a small amount of it done appropriately should necessarily be a bad idea for CO₂ reasons.)
    • CommentAuthorEd Davies
    • CommentTimeJan 26th 2017
    Orangemannot's comment is consistent with their other comments so unlikely to be intended as irony. I doubt I'm the only one to skip read with an eye roll though with a bit of sympathy on the burnt toast bit; that's the sort of bullshit that justifies people's cynicism about valid science.
    • CommentTimeJan 26th 2017 edited
    Posted By: Ed DaviesIf so, it's a completely useless statistic
    More a metric.
    It highlights two things, the vast amount of energy the world uses and that it would take about 40 years to regrow before we have another years worth.
    The problem is that it is the slow growth rate and the poor conversion from sunlight to stored fuel. PV and wind are much better options. They take up less land area per yield.

    I am not saying that we should carry on digging up fossil fuels, just highlighting that biomass is not the answer. Some technologies, such as AD are useful, but is really pretty small scale in the scheme of things (friend of mine is involved with a 6MW AD gas2gas unit from a creamery, it could be argues that not having the cream in the first place would be better environmentaly).
    This seems to be confirming my gut feel on the issue - burning wood isn't viable or sustainable as a source of heat for a significant number of UK (or global) homes. If you're burning 'waste product' wood, in an efficient burner it's justifiable from a CO2 perspective.

    <blockquote><cite>Posted By: SteamyTea</cite>I still fail to understand the argument that it is alright to burn timber in a low populations area</blockquote>

    We do things that have unpleasant by products. If we need to do them then doing so in an area where they quickly disperse to a level hot harmful to life is reasonable. It's why we moved our power stations away from the centres of our cities.

    One or more of our neighbours (London terrace) burns wood - whether in an open fire or stove I'm not sure. Their chimney is about 6m above and c10m across from our MVHR intake but we occasionally get a faint smell of smoke in the house.
    • CommentAuthorArtiglio
    • CommentTimeJan 26th 2017
    Morning Gents

    Most urban wood burners are fashion/lifestyle choices rather than being installed as a considered choice for a heat source. Again I'd suspect that in many cases they will never save any money or be used particularyly efficiently. The green benefits are talked up by owners to justify having one, rwther than just admit they enjoy the cosy glow.
    In rural areas the story is a little different, where wood may well be a homes primary source of space heating and maybe for hot water.
    My mothers property (rural wales) used lpg and woodstoves for years, mainly because my late father was a carpenter joiner working from the barns, he milled logs and dried his timber on site, so there was plenty of effectively free wood.
    She now relies on bought in forestry thinnings (15 tonne loads (wet)) which i process and is air dried on site. This feeds 3 wood stoves that satisfy the space heating for the property for probably 16 hours a day in the heating season. LPG used to do the sleeping hours , we took advantage of the RHI scheme to update the old gas system. And now have a pellet boiler.
    Getting back on topic, from my experience and having spoken with many in the biomass industry ( sorting out burn/efficiency issue) there will be looming concerns in the future regarding emissions from wood stoves and in particular pellet boilers/stoves. Many systems installed under RHI , have been done so by companies jumping on the bandwagon selling equipment that in many cases is not the " light and leave" convenience they state and nowhere near as efficient overall as they suggest.
    However the goverment don't really care, currently they are more interested in recording as much pellet/wood useage as possible in order to justify claimed greenhouse gas reductions. Emissions are currently of no interest. Once notional targets have been met , maybe this will change.
    • CommentAuthorEd Davies
    • CommentTimeJan 26th 2017 edited
    Posted By: SteamyTea…just highlighting that biomass is not the answer…
    And thinking anything is the answer is part of the problem. We need a mix of answers: wind won't do it alone, neither will solar, hydro, tidal or whatever (nuclear?) but they can complement each other to make up a sensible overall solution. So doing calculations to show that one its own won't work is just a waste of time.

    PV and wind are much better options. They take up less land area per yield.
    However, biomass does have the advantage of storing energy. If you have a reasonably efficient house (say, a not-quite-Passiv retrofit) which is supplied with all its energy needs for most of the year by solar and wind it might not, from a purely CO₂ perspective, be unreasonable to supplement those for a few months with a bit of biomass burning.

    Also, a bit of coppiced woodland provides some useful habitat - better than a PV farm. And it's not impossible to have small trees as a fuel crop on a wind farm.
    <blockquote><cite>Posted By: Ed Davies</cite>Orangemannot's comment is consistent with their other comments so unlikely to be intended as irony. I doubt I'm the only one to skip read with an eye roll though with a bit of sympathy on the burnt toast bit; that's the sort of bullshit that justifies people's cynicism about valid science.</blockquote>

    Thanks Ed, that was my point. bullshit presented as valid science.
    As for my perspective POV?
    All things in moderation, especially moderation.
    We drive a v. ordinary 6 year old diesel car, we also keep a 1998 "classic" roadworthy as backup.
    I like diesel as a fuel, its simply safer.
    I like KERO as a heating fuel, I understand it, and use it in moderation.
    I dont mind rats, even on our doorstep, as long as they stay outside, mostly!
    We waste ZERO foodstuffs, reuse stuff gleaned from skips etc, & live v. simple.
    Essentially we dont participate in the consumer driven disposable lifestyle world.
    I continue to be amused at people, professing a green agenda, looking to build on green field sites(without rats or habitat that might harbour a rat), an oxymoron if ever I saw one.
    i.e unatural sanatized nature.
    We are ALL part of the less than "perfick" natural world, this includes disease & death, especially if very premature babies and other very sick infants are very artifically kept alive, at horrendous cost.
    Most of all, I simply will not buy into the "woodsmoke is poisonous", from most probably people living in overclean sterile homes using God knows what cleaning chemicals, artificial air freshners and personal hygine products, never mind the shite bought foodstuffs they may choose to consume.
    Marcus,the hat
    • CommentTimeJan 26th 2017
    Posted By: Ed DaviesBy sustainable I mean doing something which could be sustained for a very long time
    If only everyone would use that back-to-basics definition of that devalued buzzword.
    If a scientist who lives in a log cabin with no cleaning chemicals, artificial air fresheners and personal hygiene products and who only consumed organic food stuffs brought out a study that said wood smoke was poisonous, would you believe him?
    • CommentAuthorringi
    • CommentTimeJan 26th 2017
    Posted By: SteamyTeaI still fail to understand the argument that it is alright to burn timber in a low populations area

    Firstly in most high populations areas main gas is an option, so we have to consider if it is OK for someone with access to mains gas to burn timber.

    Also in most high populations area, the timber that is burned is not seasoned correctly, and/or brought in, with many transport miles.

    A small amount of pollution is removed from the air by lots of nature systems, so provided we add pollution at a lower rate then it gets removed, we do not create too much damage. The risk to people is clearly a lot greater where there are more people. Hence burning wood in the middle of no way creates less damage then burning it in a city.
    Wot ringi said
    I burn wood for my heating and DHW. Wood is supplied from my own 'on farm' forests and I have the space and time to season it properly. Mains gas is not an option and LPG is prohibitively expensive as is oil (which here is taxed much the same as road fuel)

    So whilst I accept that burning wood causes (more) pollution than some other forms of heating at the moment I don't feel I have much of a choice.

    The government here recently said that the air pollution in winter is 50% due to wood burning. However here there is also an economic issue as wood is cheaper than gas - if you discount the labour for chopping it up and for many this is the only option. Having said that brown coal burning for domestic heating which still happens here is a lot worse than wood as it is usually burnt on older stoves (and it stinks, you can smell it half a block away).
    • CommentTimeJan 26th 2017
    @ringi @Peter_in_Hungry
    So you accept that it is a pollutant and detrimental to health
    Yes - but so is the exhaust from gas boilers - and from the production process from PV and ST, not to mention the environmental cost of producing insulation (of any sort) which I have used to reduce the amount of wood I have to burn.
    • CommentAuthorringi
    • CommentTimeJan 26th 2017
    Posted By: SteamyTea@ringi @Peter_in_Hungry
    So you accept that it is a pollutant and detrimental to health

    Yes, but so is your continued life......

    We can't stop polluting, the best we can hope for it to reduce it in as much of a cost effective way as possible. For example don't allow any burning of wood or coal etc in a property if it would cost less then £2K to get a mains gas connection.
    • CommentTimeJan 26th 2017
    Posted By: Peter_in_Hungarybut so is the exhaust from gas boilers
    Is it? I know you can often smell it (a sign of incorrect adjustment, like typical diesel vehicles) but at best natural gas produces near enough just pure CO2 and H20 - that's it's claim to fame.
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