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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.

PLEASE NOTE: A download link for Volume 1 will be sent to you by email and Volume 2 will be sent to you by post as a book.

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    • CommentAuthormike7
    • CommentTimeSep 23rd 2009
     
    Posted By: David Olivier He seems not to realise that this is thermodynamically equivalent to a large heat pump;


    It wasn't when I studied thermodynamics, if I recall correctly. Mind you, that was a long time ago ... care to refresh my understanding? ( The wiki and other ref. you gave were a bit too long to trawl through for this point.)

    I'd be very surprised if our man had made such a howler and it not be picked up before.
    • CommentAuthorjon
    • CommentTimeSep 23rd 2009
     
    Does seem to be apples and oranges though Mike?

    I'm probably biased on this one: Spent last week sorting through my late father's notes on CHP (it was his idea to introduce it into the UK)
    • CommentAuthorbrig001
    • CommentTimeSep 24th 2009
     
    Hi Jon, he allows 8% for electrical distribution losses and does say:

    "I emphasize that this critical comparison does not mean that CHP is always a bad idea. What I’m comparing here are methods for heating ordinary buildings, which requires only very low-grade heat. CHP can also be used to deliver higher-grade heat to industrial users (at 200 ◦C, for example). In such industrial settings, heat pumps are unlikely to compete so well because their coefficient of performance would be lower."

    I was surprised by the whole CHP section, because I thought it was obvious, but I think he is right because the distribution losses of heat are likely to be higher than the distribution losses of electricity in most cases.

    Bri.
    • CommentAuthorjon
    • CommentTimeSep 24th 2009
     
    hi brig

    Yes; Not sure on this one. CHP (dual reciprocating) was originally introduced into the UK for a Pharmaceuticals plant where high pressure steam lines were required for the processes (back then payback from selling to the grid was pitiful).

    He makes a good case but the case assumes that the 49% gas turbines are the supply. I suppose that if we need new turbines then at the margins, it's a good idea to do it the way he suggests. However, politicians have the habit of getting involved and we may end up with Coal doing the supply: The whole argument probably falls down if that's the case?

    Only just reading through the document so haven't had time to think about it
    • CommentAuthorbrig001
    • CommentTimeSep 24th 2009
     
    It is all a bit hard to tell because, unlike in some other topics, he has not given theoretical or likely maximum efficiencies for heat pumps or CHP. But I suppose the point is: it isn't a given that CHP is the best, and it needs to be decided case by case.

    Bri.
    • CommentAuthorjon
    • CommentTimeSep 24th 2009
     
    Agreed

    Overall, despite a few minor niggles, I think that this book was a truly brilliant exercise.
    •  
      CommentAuthorfostertom
    • CommentTimeOct 7th 2009
     
    http://www.theecologist.org/News/news_round_up/313680/renewables_expert_david_mackay_appointed_to_government.html

    >it is 'a crime to take a chemical and set fire to it simply to generate low temperature heat'

    >Mackay advocates the widespread use of ground-source heat pumps, which concentrate residual heat in the soil using electrical pumps to generate hot water for domestic heating

    >nuclear power plays a significant role in most of the scenarios of the UK's future energy mix which appear in Mackay's book

    >Previous Scientific Advisers, such as Sir David King, have proved highly influential in shaping Government policy. Sir David's legacy was world-leading policy on climate change, but also building the case for weaker regulation on GM crops
    • CommentAuthorpmcc
    • CommentTimeOct 7th 2009
     
    The best quote is 'the price of carbon dioxide must be such that people stop burning coal without capture'. Until there is a robust way to price CO2 at sufficient levels that affect everyone in the same way, we're just fiddling around the margins of the problem.

    MacKay's commentary is predicated on how to most effectively preserve our current high energy consuming lifestyles while winding down use of fossil fuels. Within those terms of reference, I have not yet come across an alternative narrative that 'adds up'.

    Some talk of just using less and adopting simpler lifestyles. But these visions tend to be vague about how to support today's over-sized populations in reasonable comfort and stability, and how to get from here to there.

    Whatever we do, there are unpalatable choices to be made. Personally I would rather we starting building new nuclear stations than playing brinkmanship with carbon capture and imported fossil fuels. And get going with some next-gen fast breeder prototypes which will eliminate the need for imported uranium for the foreseeable future.
    •  
      CommentAuthorfostertom
    • CommentTimeOct 9th 2009 edited
     
    Posted By: pmccMacKay's commentary is predicated on how to most effectively preserve our current high energy consuming lifestyles while winding down use of fossil fuels. Within those terms of reference, I have not yet come across an alternative narrative that 'adds up'.
    Succinctly put pmcc - that' was my 'impression' - but is it definitively true that that is McK's position? If so, that wd explain why the govt chooses him - assuming it's also definitively true that that is the govt's position.

    Is it that he govt is hell-bent on nuclear (to fulfill 'let us be your best friend' commitments that Tony made to George) hence must cynicallly support the above line in order to justify the need for nukes?
    Or is it the other way round - the govt and its favoured so-called science advisers (actually drawn from the very circumscribed 'big-technology' subset of scientists) haven't grasped the concept or possibility of 80% load reduction, hence have to reluctantly resort to nuclear?
    • CommentAuthorwookey
    • CommentTimeOct 9th 2009
     
    They may well have grasped the concept, but I suspect they don't believe it can be done across the board, and that the 50% reduction in consumption McKay assumes is as good as we are likely to get. I agree it's possible to do much better than that, but on average I reckon 50% is a realistic target (for total energy consumption).
    •  
      CommentAuthorfostertom
    • CommentTimeOct 9th 2009
     
    And 50% load reduction still requires nukes and C-capture coal?
    • CommentAuthorbampton
    • CommentTimeOct 9th 2009
     
    he is giving a talk at oxford brookes on the 21st if anyone's interested
    • CommentAuthorjon
    • CommentTimeOct 9th 2009
     
    Could potentially be done other ways Tom but this would require the planning system to be changed: Far easier to put Nuclear in?
    •  
      CommentAuthorfostertom
    • CommentTimeOct 9th 2009 edited
     
    Posted By: jonthis would require the planning system to be changed
    In what way - to allow houses to be built differently, or what?
    • CommentAuthorSimonH
    • CommentTimeOct 9th 2009
     
    <blockquote><cite>Posted By: fostertom</cite>And 50% load reduction still requires nukes and C-capture coal?</blockquote>

    I think that's what he's been saying. First reduce demand 50% and then on the demand that remains make it Low CO2 =~ 80% required emission cut.

    If I was serious about reducing demand, I'd first look at cars as an easy option and say, you can have any size and type of car you like, but it will be limited to 100g/km emissions from 2012. And 50g/km by 2030.

    Tough pants if you had a ferrari/lambo in mind. Unless - they actually realise that people spending £150,000+ on a car can probably afford some LiFePO4 batteries instead of a 5.0L V8. And shift the emissions to the powerplant. These exotics cars in my mind are the one which should be leading the way. It's now possible to get over 400 bhp from an 4WD battery vechicle.

    It's much harder to suddenly retrofit all houses with external wall insulation, economically and politically. Can you legislate to say by 20xx you must have done it? Do you start with people carrying out extensions, then include all houses with < SAP 50, < 60, < 70 then everyone else?

    I think we all know on this forum retrofit passive is almost possible but not quite. So a government programme for the next 5 years to do 100 houses per year with monitoring data and building up knowledge should be a starting point. If it's £20,000 per house that's only £10million to kick start the initiative before committing £billions.

    Simon.
  1.  
    Posted By: fostertom
    Posted By: jonthis would require the planning system to be changed
    In what way - to allow houses to be built differently, or what?


    I think that planning change is needed to be more open to changes in external appearance to allow the upgrade and improvement of the existing housing stock.

    It seems that the most favoured method (on this forum at least) for improving the insulation of the existing housing stock is with external insulation. Many buildings can't do this effectively because it makes the house "bigger" or changes the external appearance, which some planners won't accept. The planners need to come to accept that this is necessary and that the environmental impact will need to outweigh the cosmetic impact if we are to reduce our domestic energy usage on a large scale.

    Similar story with windows, replacing single glazing with 2G/3G etc.

    At least there is now a precedent with renewables that it is hard for them to reject on cosmetic grounds - a similar approach *may* be necessary for insulation, windows etc.

    Building new houses to a high spec. serves as useful exemplars and testbeds and is clearly part of the solution, it is still a small drop in the ocean compared to the existing housing stock.
  2.  
    Posted By: jonbut this would require the planning system to be changed


    ...line them all up...

    :devil:

    J
    • CommentAuthorjon
    • CommentTimeOct 9th 2009
     
    "At least there is now a precedent with renewables that it is hard for them to reject on cosmetic grounds - a similar approach *may* be necessary for insulation, windows etc."

    However, it's very very easy to reject renewable schemes outside development boundaries (in my county every major on-land scheme, except one or two waste-energy facilities, has been successfully opposed) and it's usually uneconomic to develop renewable energy in development boundaries. A few code 6 houses won't make the slightest dent in our energy supply needs. Plus ca change.
    • CommentAuthorSimonH
    • CommentTimeOct 9th 2009
     
    I tell ya, the best way to get renewables through if not for a large energy company / private investor to put in an application, but for someone in the community (i.e. whoever is reading this now) to sell the idea of a community owned energy station to their neigbours/village/town. Making it generate a return for those people near to it, is a lot different to just sticking it in their back yard.

    The economics of some techonologies has gotten to the point where commercial firms like pension funds are looking to invest via low carbon commmunities. At the recent Low Carbon Communities Network conference there was a company there doing just that. Due to nexy years FiT pretty much everything except PV is now investment grade - as long as someone can get it through planning. The company invovled said overall funds are pretty much unlimited - but you'll only 50% of the project will be financed - to contain their risks. Thankfully LBCP can fund the other 50% for community projects.
    • CommentAuthorjon
    • CommentTimeOct 9th 2009 edited
     
    "In what way - to allow houses to be built differently, or what? "

    No, just some real thought by interested Planning departments about what they need to be doing and promoting. As opposed to the other end of the spectrum:

    guide to Renewables for Reluctant Planning Authorities:

    First you write a Sustainability Appraisal (SEA) in accordance with European Directive 2001/42/EC ensuring that renewable energy is considered (but you ensure that it is considered as the last priority item in your list). Having established in your Sustainability Appraisal that the sustainability of the preservation of land and various other items (such as sustainability of the town centre businesses, reducing crime, townscape character, Social Housing etc) are equal to, and thus in aggregate over-ride renewable energy strategy you can then confine renewables to within development boundaries using a "Scoring matrix".

    Then, to ensure that you can't be caught out for not having one, incorporate a "Renewables Policy" into your development {boundaries] strategy

    Having done this, limit the amount of land available within development boundaries so that it would be uneconomic (and, frankly, technically daft) to proceed. Make sure that you don't specifically allocate any land to renewables or renewable/mixed-use. Even if you get caught out, it'll only be a few wind farms outside development zones that get built because the wording will say "renewable energy schemes" and will thus exclude renewable heat, multi-purpose and combined use schemes.
    • CommentAuthorjon
    • CommentTimeOct 9th 2009
     
    PS the above would be laughable if it wasn't exactly the way that the Department of Communities and Local Government tell Councils that they should do it:

    http://www.communities.gov.uk/planningandbuilding/planning/sustainabilityenvironmental/sustainabilityappraisalsa/

    Then click on "Sustainability Appraisal of Regional Spatial Strategies and Local Development Documents"
  3.  
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