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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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    • CommentAuthortony
    • CommentTimeAug 6th 2012
     
    What are our options for fuels in the future?

    My list

    1) Solar

    2) Electricity

    3)Electricity from Nuclear

    4) Solar PV

    5) Electricity from Tidal, Hydro, Geothermal, small ammount of wind and wave
    •  
      CommentAuthorfostertom
    • CommentTimeAug 6th 2012 edited
     
    Solar that isn't 'fuel', in that it's too low-grade to be packaged or piped or otherwise transmitted or sold to anyone else, but can only be used right where it's collected (where it may be stored, too).

    Low grade (i.e. no higher grade than it needs to be, for the intended use) means effortless, maybe lo-tech, but very efficient collection/conversion of incident radiation.

    As it can't be sold/transmitted, it's not a market commodity, so its 'price' won't be dragged up (regardless of 'real' cost) by substitutability with other, increasingly scarce energy sources.
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 6th 2012
     
    Posted By: tonyWhat are our options for fuels in the future?


    All of them, plus coal and gas, maybe a bit of oil too.
    How far into the future you thinking?
    • CommentAuthortony
    • CommentTimeAug 6th 2012
     
    after oil and gas get too expensive
    •  
      CommentAuthorfostertom
    • CommentTimeAug 6th 2012
     
    They'll ALL get too expensive, as substitutes for ea other, regardless f cost of production etc. So hang onto that worthless piece of woodland!
    • CommentAuthoran02ew
    • CommentTimeAug 7th 2012
     
    What about WOOD, its my only fuel in the crumble down cottage.
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 7th 2012
     
    Trouble with wood is the land area needed.
    But algae may be better, there is a lot of sea still.
    • CommentAuthortony
    • CommentTimeAug 7th 2012
     
    Andrew, the problem with wood is that there is nowhere enough of it for everyone if they wanted to use it now so we would finish up with total deforestation and no wood for anyone even if we could live through the smoke and smog.
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 7th 2012
     
    My energy use is about 4.5 MWh/year (16200 MJ)
    1 kg of timber has about 16.2 MJ/kg
    So I would need 1 tonne of timber (assuming all efficiencies are equal which they are not, hard to run my computer on wood).

    Growth of timber is around 7.5 kg per tree per year (for the first ten years).
    So I would need 133 trees.

    Tree density, for managed woodland, is 2500 trees per hectare or 4 m^2 per tree.
    So I would need at least 532 m^2.
    That would allow me to go for ten years without powering the house (while the trees grow) and then on the 11th year have it powered, which would be a nonsense. So realistically I would need 10 times that land area, 5320 m^2 (about half a hectare).

    This does not allow for any sequestration (so not improving the atmospheric CO2 levels, need another 2000 m^2 for that).

    Now lets us take a stab at efficiencies. Direct space heating and DHW could be pretty high at 70 to 80%. Electricity pretty low, probably around 20 to 30%. I estimate that I need 1000 kWh of electricity a year, leaving 3500 kWh a year for heating and water.
    So that is about 4000 kWh for electricity and 4500 kWh for heating, a total of 8500 kWh (30600 MJ). This boils down to 1900 kg of timber or 252 trees per year (tenth of a hectare @2500 trees per hectare).
    So on the rolling ten year timescale my house, with two occupants will need 1 hectare of wood land (10,000 m^2).

    Now if England has a surface area of 25000000 Hectares and assuming that half of it can be used to grow trees, then it can support 12.5 million houses like mine (25 million people). So about half of what we are at the moment.

    And that is just domestic use, take in the rest of the countries infrastructure and you are into probably a quarter of that at best.

    Even solar, with storage, will struggle.
    • CommentAuthorSeret
    • CommentTimeAug 7th 2012
     
    Posted By: tonyWhat are our options for fuels in the future?

    My list

    1) Solar

    2) Electricity

    3)Electricity from Nuclear

    4) Solar PV

    5) Electricity from Tidal, Hydro, Geothermal, small ammount of wind and wave


    Are you suggesting we pick one? The energy mix in the future will be diverse, as it is now. Gas and coal will work alongside nuclear and renewables for a long time yet, probably until reserves are depleted enough to make them uneconomical (so maybe 50-100 years for gas, 100+ years for coal). Nuclear in some form will be with us for a very very long time.

    I can see new renewables slowly increasing up to may 30-50% of electricity in the next few decades, although uptake will be highly variable around the world. I can't see hydrogen gaining much ground as an energy carrier unless we can get that figure much higher and start electrolysing in bulk, there's not much point in a hydrogen economy if we're just reforming IMO. Some suggest it would be possible using large-scale CCS, but the prospects for CCS aren't really looking that good from what I've read. All of which means transport will stay largely oil-based for several decades at least, as we need a lot of improvement in battery technology to fully electrify.
    • CommentAuthortony
    • CommentTimeAug 7th 2012
     
    An unsustainable option then
    • CommentAuthorJonti
    • CommentTimeAug 7th 2012
     
    I agree with Seret in that it will need a mixture of energy sources. Most of the comments on here seem to think that it needs to be a ONE source solution which is ill informed and narrow minded.

    Jonti
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 7th 2012
     
    If, for arguments sake, we are at Peak Oil right now, and again for arguments sake it is about $100/barrel, and for arguments sake the uptake of low carbon generation keeps pace with usage inflation and is cost compatible to oil, then the unit cost for energy, before it is adjusted for inflation, is $100/boe (5860 MJ per $100, 1628 kWh/$100 or about 6 cent a kWh or even 4p/kWh or about what we pay for gas at the doorstep).
    You can do the same with coal, probably the largest reserves and cheapest fossil fuel we have.
    If we have coal at $30/tonne, but we are only say only a 1/4 of the way though the worlds reserves and Peak Coal is say 150 years away, we cannot even a guess at what the tonnes price will be then.
    • CommentAuthoran02ew
    • CommentTimeAug 7th 2012
     
    I was just suggesting that WOOD it was missed of the initial list. Personally im with Secret it will have to be a mix of all the above.

    However if it is up to us on the GBF to find the answer then my money is on some yet undiscovered power supply from outer space, just look at the Starship Enterprice and captain kirk, they went light years and never seemed to re-fuel.
    • CommentAuthorJeff B
    • CommentTimeAug 7th 2012
     
    I seem to remember they had to stock up on dilithium crystals from time to time?
    •  
      CommentAuthorfostertom
    • CommentTimeAug 7th 2012
     
    Did anyone get my 2 points about the significance of 'non-fuel' solar collection
    Posted By: fostertomLow grade (i.e. no higher grade than it needs to be, for the intended use) means effortless, maybe lo-tech, but very efficient collection/conversion of incident radiation.
    and
    Posted By: fostertomAs it can't be sold/transmitted, it's not a market commodity, so its 'price' won't be dragged up (regardless of 'real' cost) by substitutability with other, increasingly scarce energy sources.
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 7th 2012
     
    I did Tom, but chose to dismiss it for good reasons (though I have been thinking about a way to show it graphically and without numbers)
    •  
      CommentAuthorfostertom
    • CommentTimeAug 7th 2012
     
    Oh, ta
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 7th 2012
     
    Bugger, going to have to do it now :cry:
    • CommentAuthoran02ew
    • CommentTimeAug 8th 2012
     
    Posted By: SteamyTeaBugger, going to have to do it now




    Thats the persuasive power of Tom Foster. Should of kept your head down.
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 8th 2012
     
    :bigsmile:
    •  
      CommentAuthordjh
    • CommentTimeAug 8th 2012
     
    What do you mean by "fuel"? It's often used to mean an energy source for vehicles. But perhaps you mean primary energy source? There are lots of ways to make fuel from practically any energy source.
    • CommentAuthortony
    • CommentTimeAug 8th 2012
     
    may be I should have been a bit clearer, I was thinking of a fuel that was distributable to the masses, easy to use, acceptable, non polluting, affordable, sustainable, green etc
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 8th 2012
     
    Posted By: tonynon polluting

    Hydro is out then (old news resurrected and mentioned on here before):
    http://www.sciencedaily.com/releases/2012/08/120807132306.htm
  1.  
    Posted By: SteamyTeaMy energy use is about 4.5 MWh/year (16200 MJ)
    1 kg of timber has about 16.2 MJ/kg
    So I would need 1 tonne of timber (assuming all efficiencies are equal which they are not, hard to run my computer on wood).

    Growth of timber is around 7.5 kg per tree per year (for the first ten years).
    So I would need 133 trees.

    Tree density, for managed woodland, is 2500 trees per hectare or 4 m^2 per tree.
    So I would need at least 532 m^2.
    That would allow me to go for ten years without powering the house (while the trees grow) and then on the 11th year have it powered, which would be a nonsense. So realistically I would need 10 times that land area, 5320 m^2 (about half a hectare).

    This does not allow for any sequestration (so not improving the atmospheric CO2 levels, need another 2000 m^2 for that).

    Now lets us take a stab at efficiencies. Direct space heating and DHW could be pretty high at 70 to 80%. Electricity pretty low, probably around 20 to 30%. I estimate that I need 1000 kWh of electricity a year, leaving 3500 kWh a year for heating and water.
    So that is about 4000 kWh for electricity and 4500 kWh for heating, a total of 8500 kWh (30600 MJ). This boils down to 1900 kg of timber or 252 trees per year (tenth of a hectare @2500 trees per hectare).
    So on the rolling ten year timescale my house, with two occupants will need 1 hectare of wood land (10,000 m^2).

    Now if England has a surface area of 25000000 Hectares and assuming that half of it can be used to grow trees, then it can support 12.5 million houses like mine (25 million people). So about half of what we are at the moment.

    And that is just domestic use, take in the rest of the countries infrastructure and you are into probably a quarter of that at best.

    Even solar, with storage, will struggle.


    Sorry Steamy but your so way off the mark for annual usage of timber but I can understand your logic to get such unrealistic figures. Your making the classic error of starting with an annual fuel consumption and then trying to fulfill that consumption with a single fuel in this case wood. If you used solar and thermal oil than you could satisfy in the region of 90% of your annual consumption leaving only 10% required from biomass. The key word being biomass rather than wood. Add to that all the biomass you currently throw away (Newspapers. Cardboard packaging, ) Change your toilet for a dry sawdust toilet and your wood requirement reduces to just 5% which should easily be achieved by shredding the woody material pruned annually from your garden.
  2.  
    Posted By: tonyAndrew, the problem with wood is that there is nowhere enough of it for everyone if they wanted to use it now so we would finish up with total deforestation and no wood for anyone even if we could live through the smoke and smog.


    We have plenty of wood if used efficiently in micro CHP units like the Otag Bison what we dont have is timber to fuel dinosaur power stations like Stevens Croft at 25% efficiency.
    • CommentAuthortony
    • CommentTimeAug 9th 2012
     
    Are you saying that there is enough in the UK for everyone to use CHP?
    • CommentAuthorJoiner
    • CommentTimeAug 9th 2012
     
    John, is there any info in English on the Otag Bison system?

    (Appears that the Naviron lot are experiencing the same language problems.)
    •  
      CommentAuthorSteamyTea
    • CommentTimeAug 9th 2012
     
    Posted By: renewablejohnYour making the classic error of starting with an annual fuel consumption and then trying to fulfill that consumption with a single fuel in this case wood

    Hardly a classic error, just highlights the difficulty of a single fuel.
    Not really valid to use brought in waste as that has to come from somewhere and will have an associated land area connected to it.

    I hardly see how using garden waste in a composting toilet will reduce my energy usage to 5%, have I missed something?
    • CommentAuthorSteveZ
    • CommentTimeAug 9th 2012
     
    What I would like to see as our energy system: there must be more but these will do to start

    Baseload Supply
    Nuclear option
    Spend money (a few Ă‚Â£billion) on research and actually develop a standard Molten Thorium Salt Reactor. Factory built at truck trailer size so no more big nuclear sites, just lots of fail-safe small ones. Licence the design world-wide to avoid monopolistic problems. Use up the existing high-grade nuclear waste in them. Thorium is widely distributed around the world, especially in India, which is short of Uranium ore. There is more Thorium ore buried by the US government now than we could use in a 1000 years at present energy consumption rates.This would also remove the US moratorium on the use of rocks containing Thorium to obtain the Rare Earth Metals associated with Th, so the world's supply of REMs would vastly increase

    Geothermal power plants where the geology is suitable. Small surface footprint and almost a closed system. They can use and recycle water for high temp areas or a binary system if the temp is too low for water

    Waste Pyrolysis, not incineration or Anaerobic digestion. A closed system producing more than the power it uses to run itself, plus useful fuel gas or liquid fuel via a small scale Fischer-Tropf reactor, and a valuable bio-char by-product. Raw material could be a problem if we really get to grips with recycling, but I don't think it's going to happen any time soon

    Reliable intermittent
    Tidal turbines around our coasts, given the daily variance in local tide times it is almost continuous. Out of sight but need regular maintenance

    Intermittent
    Solar farms and small scale domestic and commercial. Marginal in this country but pretty good where the sun shines regularly
    VAWT windfarms - early work on closely-packed VAWTs indicates an energy per unit area covered ratio several times higher than a typical HAWT. They don't need to be very high and don't produce the noise associated with HAWT tip speeds and their gearboxes, so might be more acceptable in more places

    What I suspect we will get, courtesy of vested interests and political short term thinking

    More conventional nuclear. possibly with added Beryllium to increase the heat transfer and prolong the fuel rod life
    Lots of Shale gas, natural gas, coal, possibly with CO2 capture
    More damned HAWT wind turbines

    Nothing like a good rant, is there?
   
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