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Green Building Bible, Fourth Edition
Green Building Bible, fourth edition (both books)
These two books are the perfect starting place to help you get to grips with one of the most vitally important aspects of our society - our homes and living environment.

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    • CommentAuthorfuncrusher
    • CommentTimeApr 29th 2007
     
    We own over 50 acres of woodland, so firewood is continuously available- and yes, we manage the woodland to make best use of the timber and replant continuously. HOWEVER, I am not really convinced that wood-burning is a sensible eco-option when all factors are considered.
    On the old forum there was debate about the CO2 cycle. Summarising, the argument 'for' was that woodburning simply returned to the atmosphere the carbon previously absorbed by the growing tree, and which would anyway be liberated by decay. The argument 'against' was that burning fossil fuels was doing exactly the same thing, but with a time lag of a few million years, and anyway an unfelled tree would carry on absorbing more carbon and there was no guarantee that burned wood would be replanted.
    However there are I think two further arguments against. Firstly, burning timber produces far more gases than just CO2. There is a whole range of nasty toxic compounds emitted, depending on the temperature. Overall, wood smoke is a very dangerous carcinogen. Secondly, wood left to rot returns humus to the soil and also supports both directly and indirectly an immense array of fauna and flora in the rotting process. Sanitised woodland denies bats, bird, fungi, insects, bugs and ferns etc homes and /or food which abound in dying or rotten trees.
    Perehaps at best there is only a case for burning timber which is being discarded after a useful life in buildings, furniture etc?
    • CommentAuthorMrT
    • CommentTimeApr 30th 2007
     
    I think it depends on the circumstances. In rural areas with good supplies then its a good choice. But the wood
    has to be froe m well managed woods, well seasoned, air dried for at least 2 years before burning(some wood like ash seasons quicker). The stoves must be high efficiency. I use an old villagers stove which is fitted with a damper on the flue, this damper slow down the burn rate so I never use it. People like to leave stove in over
    night on slow burn but this is not efficient. I'm looking at getting another stove for my kitchen which will produce
    DHW. Sadly heating the water will impair the clean burn as most of the sotves I've seen have the boiler in the fire box.

    Yes wood is a good source of fuel but steps must be taken to avoid loss of habitat, conservation of supply and efficient burning.
  1.  
    I don't believe wood burning stoves in rural areas are likely to cause any health problems, concentrations in the air at ground level would never get high enough, and the availability of locally produced wood fuel is attractive. BBQs and burning prunings etc in the garden is a worse risk because you haven't even got a flue to get the smoke above roof level. In an urban area it is a different matter and we have seen the effects of widespread burning of solid fuels in the smogs that were common before the Clean Air Act.

    I don't agree with chopping down trees specifically for firewood, growing trees are far too valuable a resource, but firewood is a good use for off-cuts, thinnings and scrap timber and forms part of the traditional pattern of woodland management. There is no "magic bullet", pollution free energy source. Best that we can do is develop a range of options each of which can play a part in replacing some of the energy we currently get from fossil fuels.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 10th 2007
     
    www.bdonline.co.uk/story.asp?storycode=3093022&origin=BDweekly
    • CommentAuthorTerry
    • CommentTimeAug 10th 2007
     
    As Chris says there is no clean energy source - solar panels, wind turbines, hydro-electric etc all require infrastructure, components and maintenance which in turn require mineral extraction, transport, manufacturing, instalation etc.
    As with all forms of energy generation we need to do what we can to limit the impact.
    • CommentAuthortony
    • CommentTimeAug 10th 2007
     
    Is no one concerned about all the instant CO2 that is produced from burning this wood? Or the other pollutants?
  2.  
    I'm very concerned about the instant CO2 of burning down the rain forests which is a massive source of emissions. I don't think it is a bad thing to burn scrap wood, forestry thinings, off-cuts etc for fuel. If we didn't they would just rot on the ground or in landfill or be burnt on bonfires producing emissions anyway.

    I'm not bothered about the other pollutants. If they were that bad Ray Mears would be dead already.
    • CommentAuthorGBP-Keith
    • CommentTimeAug 11th 2007 edited
     
    The long and the short of it is that we need fuel of some kind and wood/biomass is the most easily sustained carbon supply within human timescales.

    Our goal has to be to educate everyone to burn it sensibly - adequate drying and super-efficient boilers.

    A strong argument in favour of woodburning is that personally, I have trebled the acreage of land under woodland cover on my farm (and I certainly will not sanitize it all) because of my desire to use more wood and this kind of positive action is becoming more commonplace in society generally whereas previous generations were just clearing woodland as nuisance.
    • CommentAuthorMrT
    • CommentTimeAug 11th 2007
     
    Burning wood is more sustainable than gas or coal. Burning wood from sustainable supplies enhances the environment in as much as it puts money into woodland management.

    My supplier, FSC certified is a forester who looks works on huge areas of woodland is devon/somerset. A certain amount of wood needs to be cleared to maintain the balance of light and also preserve the area for tourism etc. All of the logs I got this year have been seasoned for 2 years and is beech wood cleared because of the drought conditions of recent summers affected the roots making the trees dangerous as they were on road sides and pathways. It would be a shameful waste not to utilise this as a resource. Also much of the firewood comes form coppice woods where the trees are pruned and therefore continue to remove CO2 from the atmosphere.

    Personally I would like to see more of the UK converted to woodlands. To much land is occupied by the meat industry. Maybe if we cut down on meat production we could grow more trees and crops.

    As for pollution. Why is wood burning worse than coal gas? You can get dry seasoned wood, also efficient stoves are available. More should be done to encourage clean burn technology.
    • CommentAuthorbiffvernon
    • CommentTimeAug 11th 2007
     
    If the problem is as great as some of us believe, and we have to not only stop adding carbon dioxide to the air, but also have to remove the CO2 already added, then what may be the best way to do this is to grow timber specifically for burning and capture and store deep underground, the CO2 evolved during combustion. The process of photosynthesis - combustion - flue gas - capture - storage looks likely to be the most practicable route, and the heat energy produced is a bonus.
    • CommentAuthortony
    • CommentTimeAug 11th 2007
     
    The problem with that scenario Biff is the last bit -- it gets burnt again not stored -- ever increasing interest in wood burning means more and more CO2 is released and less and less left stored in wood.
    • CommentAuthorGBP-Keith
    • CommentTimeAug 11th 2007 edited
     
    That is not true Tony. As I said I have three times more trees planted her at the farm now than ten years ago. Probably three times more than I will need to harvest for my wood burning uses and this has been planted on ground that was previously top grade grassland where cattle used to fart and poo all over. And all around I see others are starting to do similar. it is called foresight I think. All be-it perhaps misguided.

    We plan to plant 75% of the farm with native woodland before leaving. That alone would be enough to sustain the wood boilers of a small community if necessary.

    What Funcrusher failed to address in his opening speech is the true societal cost of a fossil fuel addiction - war and terror

    High-tech stuff like heat pumps will do little to ease the cold turkey.
    • CommentAuthorbiffvernon
    • CommentTimeAug 11th 2007
     
    What I was talking about was storing the CO2 after the wood is burnt. It is using the trees as CO2 atmospheric scrubbers. This actually works better than artificially trying to get the tiny amount of CO2 out of the atmosphere. It is relatively easy to capture CO2 from the flue gas where it forms the bulk of the gas.

    If we have already released more CO2 into the air than is safe, this may be the best route.
  3.  
    Is it practical to scrub CO2 from flue gases in small boilers and CHP plants? You've then got to get the CO2 to the North Sea or some other place where suitable underground storage exists. I'm guessing this will only be economic in large power plants??

    No reason why we need to burn the timber to use forestry as a carbon sink. We could just plant a whole lot more durable timber and, when it is mature, use it for making high quality furniture and in long lasting buildings. The CO2 is then locked up indefinitely. First step is to stop burning the rain forest down though or else we are urinating into a hurricane force wind.
    • CommentAuthortony
    • CommentTimeAug 11th 2007
     
    A lot of people burning a little wood = more CO2 than that which comes from the rain forests.
  4.  
    I don't know about that Tony, but I have read that forest fires made up 40% of greenhouse gas emissions one year earlier this decade (remember when a large part of South East Asia was shrouded in wood smoke for weeks on end). A lot of people already burn a little wood each day, indeed the majority of the world's population.
    • CommentAuthortony
    • CommentTimeAug 11th 2007
     
    So should we be advocating joining them?
    •  
      CommentAuthornigel
    • CommentTimeAug 11th 2007 edited
     
    Posted By: tonySo should we be advocating joining them?


    And what should we be using instead?

    Advocating not using wood is fine providing you can advocate a better alternative.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 11th 2007
     
    Posted By: biffvernonThe process of photosynthesis - combustion - flue gas - capture - storage looks likely to be the most practicable route, and the heat energy produced is a bonus
    I hadn't quite thought of it like that - neat.
    Posted By: Chris WardleNo reason why we need to burn the timber to use forestry as a carbon sink. We could just plant a whole lot more durable timber and, when it is mature, use it for making high quality furniture and in long lasting buildings. The CO2 is then locked up indefinitely
    That's equally good Chris - buildings are a prime place to lock away unoxidised HC--- hydrocarbons (timber and other biomass, hemp husks etc) nice and dry and warm so they don't rot (oxidise back to CO2 and H2O) for the forseeable.
    • CommentAuthorbiffvernon
    • CommentTimeAug 12th 2007
     
    There's no one magic bullet to saving the species - we've got to do lots of different things. But it is clear that domestic heating with woodstoves is a lot closer to carbon neutral than using fossil fuels. The serious atmospheric carbon scrubbing would, of course, work best on a non-domestic scale.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 12th 2007
     
    Posted By: biffvernonIt is using the trees as CO2 atmospheric scrubbers. This actually works better than artificially trying to get the tiny amount of CO2 out of the atmosphere. It is relatively easy to capture CO2 from the flue gas where it forms the bulk of the gas
    This also is a good way of looking at it - provided the woodburning is instead of, rather than in addition to, burning other kinds of fuel (fossil) that haven't recently scrubbed their carbon content out of the atmosphere.

    The latter (in addition to) is of course what's going to happen - all growth of renewable, nuclear etc energy supply will be gratefully lapped up by an energy-hungry world while oil will continue to be burnt just as fast as it can be produced - and it's being produced today faster than ever before and will continue to rise till it peaks somewhere in the next 10yrs. There's probably still as much fossil fuel going to be burnt over the next 50yrs as has been burnt in total so far - so get scrubbing!
    • CommentAuthorbiffvernon
    • CommentTimeAug 12th 2007
     
    I doubt whether we'll see much rise in oil production from now on. It seems to be bumping along a plateau at around 85 million barrels per day. Light sweet crude has already peaked and we're probably at about the peak for all liquids. Time will tell. But yes, if we're at peak now, that implies we've had about half the oil (the easy half) and we will burn the difficult half over the next half century. The rate of production is perhaps more important than the final total, but as you say, there's virtually no chance of using oil at anything less than the depletion curve allows. That might still restrict CO2 levels to around 450ppmv which might give about 2 degrees C of global warming but positive feedbacks are a big unknown. Further expoitation of coal, oil shales and tar sands adds to the problem, but again it is the rate of burn that counts rather than the final amount. There is a lot of uncertainty about how quickly coal and the unconventional oils can be exploited.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 13th 2007
     
    Posted By: biffvernonIt seems to be bumping along a plateau at around 85 million barrels per day. Light sweet crude has already peaked and we're probably at about the peak for all liquids. Time will tell
    My guess is that it's a temporary plateau.
    Posted By: biffvernonThere is a lot of uncertainty about how quickly coal and the unconventional oils can be exploited
    As oil price really begins to go up and up steadily (which hasn't quite taken hold yet), driven not by supplies running out but by demand (China etc) rising fast, then it gets economic to extract these unconventionals and I think the growing demand will be partly met, i.e. production growth will resume. In fact, as price rises and rises, the peak could be postponed for quite a while. However oil eventually will become too expensive to burn as cheap fuel, reserved only for mobile fuel i.e. air and surface transport, and for chemical feedstock.
    • CommentAuthorbiffvernon
    • CommentTimeAug 13th 2007
     
    The plateau is certainly temporary, but then the curve goes down, not up. We know the depletion rates of many of the mature oil fields, we know the rate of discovery of recent years, we know how long it takes to bring new production on stream, and there are known unknowns in secretive places like Saudi Arabia that cannot add up to the gap between the business as usual demand and the possible rate of production, even when unconventional sources are included. The future is best forcast by doing the arithmetic rather than guessing.
    •  
      CommentAuthorfostertom
    • CommentTimeAug 13th 2007
     
    OK, that's good news. Means the price will go up even more steeply and oil will become unaffordable as static fuel all the sooner. But that of course means coal will return (no shortage of that).
    Posted By: biffvernonThe rate of production is perhaps more important than the final total
    Another important point - but that rate of production must include coal.

    Anyway, all that we enlightened ones achieve by a) demand reduction and b) substitution of renewables for fossil burning, will have no direct effect on slowing the global rate of production/burning of fossil fuels, because if we're consequently consuming less, the spare will just be gratefully soaked up by the fuel-hungry developing world - in fact all we'll achieve is to slow the rate of fossil price increase a bit, for their benefit!

    That's not to say we shouldn't pursue a) and b), but do it c) to get out of Putin's power, d) to no longer need to rape the Middle East, Nigeria etc, d) as a practical way for the unenlightened to rediscover Gaia, how we're part of her, and treat her with some respect, or to put that another way, e) get our own house in order.

    I'm sure that humans' long-term future is to resume harnessing ever-increasing quantities of energy (nothing's going to stop us heading out for the stars) but just now we have to take a step back and learn how to do so without fouling our own nest, wherever that may be - and that's actually a state of mind, of awareness, of consciousness - spiritual in fact. That's our present task, in these 2 or 3 decades, and it's going well in my opinion.
    • CommentAuthorbiffvernon
    • CommentTimeAug 13th 2007 edited
     
    You're right about our complete inability to slow the rate of oil burn. No amount of campaigning against airtravel will allow us to beat the oil depletion curve.

    But coal is also a finite resource and the commonly held view that there is 'no shortage of that' is way off the mark. Peak Coal will follow hard on the heals of Peak Oil. For an up to date review of the latest reports of world coal see Coal: The Roundup, by Chris Vernon at http://europe.theoildrum.com/node/2726
    •  
      CommentAuthorfostertom
    • CommentTimeAug 13th 2007
     
    More good news.

    BTW, a far higher priority than giving up air travel, is that we should all give up cement and concrete. The cement manufacturing industry - just manufacturing, not using - produces more CO2 than the entire air industry, manufacture and operation, and is rising just as fast. But anti-air-holidays is a far easier target for the self-righteous and puritanical, than the other. If there's one kind of thing our precious fossil reserves should be used for, it's life-enhancing stuff like cheap travel. Not all travellers are drunken Benidorm-bound, who couldn't tell if they were still in Bradford. Imagine a world where overseas travel was only available to politicians, business, military and media. It's the fact than everyone can go and see for themselves, that now limits the ancient tradition of spreading lies and myths about foreigners, for god knows what motives.
  5.  
    Posted By: fostertomMore good news.

    BTW, a far higher priority than giving up air travel, is that we should all give up cement and concrete


    Do you have a proposal for something [available in sufficient quantities] we can use instead?
  6.  
    I don't see how cheap air travel is particularly life enhancing Tom. Make it cheap and we just take it for granted and start going on stag dos in Prague etc. Most people who travel on cheap flights are after a good sun burn and cheap ale. They could be doing the same in the UK now we have Wetherspoons and tanning booths on every street corner. I would think it more life enhancing for people in developing countries to have a bit more of a share of the fossil fuel pie. Why can't we level the playing field and tax all carbon fuels equally?

    Concrete is really useful stuff but I do agree that we should be using a lot less of it. I still don't understand while we have to have such monolithic footings under everything we build these days. Go back 100 years and they just chucked some flat bits of stone in a trench and bricked off that. I think compressed earth blocks made on site could make real in roads into embodied energy in building by replacing bricks and concrete blocks. I'd like to see this research more thoroughly and then put into practice in the UK particularly as we have such poor structural timber resources.

    Please explain, Tom, how you think things are "going well" because all I see is things going badly and its starting to depress me... I could do with cheering up a bit....
    •  
      CommentAuthorfostertom
    • CommentTimeAug 13th 2007
     
    Posted By: Chris Wardlewe just take it for granted and start going on stag dos in Prague etc
    Speak for yourself?
    Posted By: Chris Wardlethey just chucked some flat bits of stone in a trench and bricked off that. I think compressed earth blocks made on site could make real in roads into embodied energy in building by replacing bricks and concrete blocks. I'd like to see this research more thoroughly and then put into practice in the UK
    That's the right sort of answer to yr Q, Mike George.
    Posted By: Chris Wardleexplain, Tom, how you think things are "going well" because all I see is things going badly
    Read The Crisis Point by Ervin Laszlo, ignore a great deal of naive "everybody should be good" and an eco-crisis summary that's better left to Al Gore, but the core is right - we're experiencing the ever-faster and more extreme oscillations that occur in the ultra-sensitive Decision Window just before the Crisis Point of Systems theory - where Crisis doesn't necessarily mean Bad - it just means that everything after is an unimaginable leap into something unprecedented - like the moment when a pre-human made the first tool. He puts it at 2012 and I get that feeling too, not just cos the Mayans said so. Like the tool-making moment, it's not just a technological leap but a quantum leap in awareness - like what comes after mere self-consciousness, which we've been exploring for the last million, or50k yrs or whatever? We on this forum are a small part of a global awareness of a new kind, that's rapidly reaching critical mass, thanks to the likes of George Bush, who's kindly made the issues starkly visible.
   
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