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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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    • CommentAuthormarkocosic
    • CommentTimeApr 26th 2015
     
    Use fuelly.com rather than EU emissions figures ST - more accurate for real-world economy.


    Beware the Auris Hybrid, like the Prius and all Toyota hybrids, is LESS efficient at UK motorway speeds than a standard car. In town where you'd be riding a bicycle it's great, but on the open road they're pretty poor.


    EU test cycles average 19 mph for urban use (no traffic!) and 39 mph for extra-urban (no motorways!).

    Power requirements to overcome aerodynamic drag are proportional to the CUBE of the speed. Slippery vehicles REALLY shine at motorway speed.

    Mercedes S-Class - Cd 0.25
    Audi A6 = Cd 0.26

    A Toyota Prius is also Cd 0.25 but has that inefficient powertrain for use at open road speeds. An S-Class or A6 will match/beat the economy. (Prius @ 100 mph drops to high 20s mpg)


    That little Honda Insight still returns 50 mpg at high speed cruise. ;-)
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 26th 2015 edited
     
    Posted By: fostertomOi I'm all left out - is that because
    Yes, but I shall include you in the next batch of figures.


    Posted By: markocosicUse fuelly.com rather than EU emissions figures ST - more accurate for real-world economy.
    I am trying to keep things as consistent as possible. Nearly everyone I know has either a car that seems better than a normal one, or a lot worse. Official figures are good enough for this, it is only a comparison and more to do with showing that energy use for a 'household' and spending money to save 'household' energy may sometimes be misplaced.

    I could easily go unemployed and save a lot of energy, but I am not thinking about doing that, so I shall have to stick with my high mileage (last year I actually did a lot more miles, near 40k, but it was an exceptional year).
    • CommentAuthormarkocosic
    • CommentTimeApr 26th 2015
     
    Official figures are never pessimistic...
  1.  
    1: What is your present car (make, model, trim, fuel type, age)

    Seat Altea, Stylance, 2.0ltr, Diesel, 9 years old. Tows my max AUW 1400kgs trailer and fits 2 big adults in back.

    2: Annual Mileage

    9,000pa avg over 9 years

    3: What vehicle are you thinking of getting next

    If this car doesn't last another 9 years something very similar, if it does maybe see 5 below!

    4: Dream 'Eco' Vehicle

    That BMW thing with fold up doors.....well it does have batteries doesn't it....

    5: Dream Vehicle

    Audi RS2 (ie 1995)
    • CommentAuthorCWatters
    • CommentTimeApr 26th 2015 edited
     
    As a family we run two cars....

    Ford Galaxy 1.9 Diesel - around 20,000 miles a year @ 40-42mpg
    Ford Fiesta 1.0 Petrol - around 6,000 miles a year @ 38-40mpg

    Most of the mileage in the Galaxy is due to the school run which is about 70 miles a day. No public transport available.

    Considering replacing the Fiesta with an electric car and using that for the school run. Always a rush to get to school. Due to nature of the roads it needs to cruise comfortably at motorway speeds. Carry 3 adults, two guitars in hard cases, rugby kit etc.

    Given that manufacturers bend the truth about the range what figure do I really need to see on the data sheet before taking the leap? Ideally I would like it to cope with something like this on a daily basis..

    Overnight charge
    40 mile drive mostly at motorway speeds
    Possible 2-3 hour period on charge at home
    40 mile drive mostly at motorway speeds
    Some contingency (say 5-10 miles) for detour?
    Some contingency for aging or cold batteries?

    Doesn't exist yet (as a pure electric) ?
    • CommentAuthorgravelld
    • CommentTimeApr 26th 2015
     
    Thanks for putting the numbers together ST.
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 26th 2015 edited
     
    A quick update to the chart.
    At £1.20/litre, every 8,500 kWh costs about £1000/year.
      Cars GBF 1.jpg
    • CommentAuthorDandJ
    • CommentTimeApr 26th 2015
     
    It would be nice to save all that energy and money but until they come up with a decent super efficient van to get to work in there aren't many options. I would love an electric Peugeot Partner but would get no work done as I'd be on stop charging it half the time.
    •  
      CommentAuthorfostertom
    • CommentTimeApr 26th 2015
     
    Interesting that almost all of us are doing half the mpg of the Auris - very consistent.
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 26th 2015 edited
     
    Not really surprising as the Auris does nearly 80 MPG. The figure for my car is 51.

    The main thing is that we can save a lot of energy by just changing to a more efficient car. I am not suggesting that we all go out and get an Auris, a Peugeot 308 can do pretty good mileage, and they are cheap to buy. Get a 2010 model for £6K. Probably last 5 years and with my mileage it would save me the purchase price.
    No matter how much I spend on the house I cannot save that amount, most I can save is about £500/year.
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 27th 2015
     
    This is the CO2 emissions charts, no surprises. Be interesting to see what level people think it is worth changing a car.
    I emit 1.8 tonnes a year driving, a quick calculation on my house shows that I use 2.25 tonnes (though probably less as I use night storage).
    I would think that below a tonne a year is pretty good for the time being, though half a tonne would be better.
      GBF CO2.jpg
    • CommentAuthorGarethC
    • CommentTimeApr 27th 2015
     
    I'm worried that the official figures are relatively less realistic the greater the official MPG. In my Fabia, official mpg of 83 (I think), I only managed 62mpg. In my Superb, official mpg of 66 (again need to check), I manage 55mpg.
    • CommentAuthorHairlocks
    • CommentTimeApr 27th 2015
     
    My figures look wrong, which one is which (I think you have the fabia as 1600 miles not 16000 miles a year).
    I also only get a reported 62 mpg out of the fabia.

    AS for the discovery I can't tow 3.5t with an Auris, or fit huge amounts of stuff in it. (my 4000 miles in that car is a complete guess as we have only just bought it, should be lower.) So comparing to the Auris is pointless.

    Please could you do a graph comparing to the tesla S.
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 27th 2015 edited
     
    There has always been controversy about official figures, no one seems to like them or trust them. Would you trust your neighbours to know what they are getting from their cars, probably not. So they are the best we have to work with at the moment. There are a few websites that claim to report user figures, but that is a self selecting group, so probably just as unreliable.
    I shall stick to official figures, others can work out there own mileage and do the sums if they want. Bob Monkhouse used to do a joke about his neighbour taking fuel out of his new car at the end of the month.

    The main point I am making is that for a lot of people (not so much us on here), is that a new car will have a greater energy reducing and emission reduction than solar panels and a new boiler. Each person really needs to do their own numbers and make their own minds up.
    If you work for a company that has a fleet of 'rep mobiles', then a big difference can be made.

    The Tesla Model S seems to be a pretty popular 'eco dream vehicle' (I am not getting into the solar jets), so I looked at the figures. Depending on the batteries, 70 or 85 kWh, you get between 240 and 265 miles per charge.
    That is about 3.2 miles/kWh. Using 40 kWh/Imp Gallon, then the Tesla does the equivalent of 130 MPG. With out current electrical grid mix the emissions are 87 g CO2/km. So impressive on fuel, not so great on CO2. It would still take me a day to get to my family though because I would have to recharge.
    • CommentAuthorEd Davies
    • CommentTimeApr 27th 2015
     
    Posted By: SteamyTeaWith out current electrical grid mix the emissions are 87 g CO2/km…
    We can resurrect an old thread to discuss this if anybody wants to go into it but I'd just like to point out in passing that I think the grid mix is irrelevant; the emissions for an electrical item should be worked out on the marginal emissions of the grid - the emissions which result from the extra consumption which, with the current grid, comes from gas mostly and coal a bit. This decreases the attractiveness of electric cars for now.
    • CommentAuthorMikel
    • CommentTimeApr 27th 2015
     
    1: What is your present car (make, model, trim, fuel type, age)

    Ford Focus Mk 2.5 Zetec, 1.8 Petrol, Jan 2010
    VW Autosleeper HiTop Camper short wheelbase 2.5 Tdi, Diesel, Aug 1998

    2: Annual Mileage

    Focus 7000 pa, measured fuel consumption 38 mpg
    Camper 4000 pa, measured fuel consumption 33 mpg

    3: What vehicle are you thinking of getting next

    Changed our 2000 Focus 1.8 petrol in May 2013, so not thinking of changing for some time. I looked at newer models, VEL rates, official consumption figures versus real world consumption figures and depreciation costs before replacing like for like. Will hang onto the camper as long as possible.

    4: Dream 'Eco' Vehicle

    Long range electric hatchback.

    5: Dream Vehicle

    Not really bothered about this.
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 27th 2015
     
    Mike
    Your dream vehicle is the camper isn't it :wink:

    I shall pop your data into the spreadsheet when I next update it.

    Ed
    Yes, it is marginal emissions, unless we all change to EVs/PiHs.
    It may be possible to assume some time of day charging times, say 2 hours mid morning and 5 hours at night and work from that, but as you say, it is for the other tread.
    • CommentAuthorMikel
    • CommentTimeApr 27th 2015
     
    ST,

    The camper used to be the dream vehicle and our current one is good for the two of us and the best we've had. However, we are not getting any younger and I can foresee that in time it will have to go, but hopefully not for a few years yet!
    • CommentAuthorBeau
    • CommentTimeApr 28th 2015 edited
     
    1: What is your present car (make, model, trim, fuel type, age)

    Ford Fiesta 1.4 TDCI 2008

    2: Annual Mileage

    10K

    3: What vehicle are you thinking of getting next

    Just changed last week no ideas yet

    4: Dream 'Eco' Vehicle

    The best small Diesel about if that's eco

    5: Dream Vehicle

    Kubota 4WD 70HP tractor (for the farm honest)

    As for book MPG figures I am completely confused.
    We have just got the Fiesta with 60k on the clock. The combined MPG is supposed to be 64 MPG and the clock says it has been averaging 58MPG and have already managed 64 MPG around our Devon lanes so pretty close all things considered.

    Now my rant. Needed a pickup for work and after much consideration went for a new Isuzu Dmax at great expense due to it's supposedly market leading fuel efficiency of 38 MPG combined. I can't get anywhere near this figure however I drive it :devil:
    • CommentAuthorTriassic
    • CommentTimeApr 28th 2015
     
    1: What is your present car (make, model, trim, fuel type, age

    Qashqia 1500 n-Tec, 3 years old

    2: Annual Mileage

    17k

    3: What vehicle are you thinking of getting next

    I'll be keeping this one for at least another 7 years, so no idea what next.

    4: Dream 'Eco' Vehicle

    I have no interest in cars, they are a necessary evil for rural living.

    5: Dream Vehicle

    Good second hand Mini digger, 3 sizes of bucket and a pecker.
  2.  
    Not looking very good for me!

    I might have to re-consider my objection to diesel engines. However I have always thought that particulate filters were a con job, a way of catching and holding particulates from going out the exhaust for the duration of the official bench tests and then releasing them later.

    In the study I posted on the previous page, here's the link again

    http://www.theicct.org/real-world-exhaust-emissions-modern-diesel-cars

    only one diesel Euro 6 "compliant" vehicle tested actually met the standard when tested in the real world, but unfortunately they do not identify what vehicle it was, does anyone know?

    Is there any other "real world" test data available for Euro5a vehicles? So that one could compare 4 - 5 year old diesels?

    If I were to buy diesel, based on price and availability I would probably go for either a Skoda Superb Estate or a Volvo V70 II DrivE.

    To compound my shame the company I have started work with makes carbon fibre interior trim, roof skins etc. for various European car manufacturers for their high end sports cars of the type that probably needs a small forest planted to offset the carbon impact of each one, although in mitigation they do also hold a patent for a rather snazzy 12 metre diameter parabolic solar concentrator that is in development at the moment.
    •  
      CommentAuthorfostertom
    • CommentTimeApr 28th 2015
     
    The carbon fibre components (like plastic insulations) are effective sequesterers of ex-oil carbon, which would otherwise have been burnt. It's true tho, that same amount of oil still gets burnt regardless, so no actual reduction in extra fossil CO2 going into the biosphere.

    However, at first approximation, carbon fibre results in little extra fossil CO2 going into the biosphere. Compare with same components with same made of any other (non plastic) material, and the latter would result in massive fossil CO2 addition to the biosphere.

    So carbon fibre wins, by a small head. Now, source the carbon from atmospheric CO2 instead of from oil, and you then have true and significant sequestration.

    The only doubt is about disposalk/recovery/recycling of carbon fibre at end-of-life - AFAIK no one has any idea how - so straight to landfill. The latter not bad, because it presumably it doesn't rot but stays sequestered, until such time as technology and scarcity/cost of virgin feedstock make quarrying and processing the stockpile, feasilible.
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 28th 2015
     
    You sure Tom
    CF takes about 80 kWh of energy to make 1 kG.
    Then there is the resin, a typical epoxy takes about 40 kWh/kg.

    So pretty energy intensive.

    Steel is about 5.5 kWh/kg
    Aluminium 43 kWh/kg

    Carbon fibre is made by heating a strand of polyacrylonitrile until all the non carbon molecules are expelled. It don't start as a pile of shoot and gets squished together.
    •  
      CommentAuthorfostertom
    • CommentTimeApr 29th 2015
     
    Wow - not what I picked up when I went to a seminar at the Bristol National Composites Centre recently. Not that the seminar was about CF (it was about failure of buildings to meet their expected energy targets). Valuable basic info - thanks.
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 29th 2015
     
    Go back and tell them!
    • CommentAuthorowlman
    • CommentTimeApr 29th 2015
     
    Interesting figures ST, but the material density and it's use in practice off sets some of those differences; e.g. a bike frame. On reflection maybe not enough though.
    When it comes to energy saving very little comes without a price.
    • CommentAuthorGarethC
    • CommentTimeApr 29th 2015
     
    What is is about processing aluminium that makes it so much more energy intensive than steel?

    Is the difference vs. steel offset by the 'endlessly recyclable' and longer lasting nature of aluminium products I wonder?
    • CommentAuthorCWatters
    • CommentTimeApr 29th 2015
     
    I did some work with composites 20 years ago. As I recall epoxy resin is considered "probably a carcinogen".
    • CommentAuthorowlman
    • CommentTimeApr 29th 2015
     
    I guess the vast amount of electricity needed to smelt aluminium may be one reason Gareth.
    •  
      CommentAuthorSteamyTea
    • CommentTimeApr 29th 2015
     
    Posted By: owlmanInteresting figures ST, but the material density and it's use in practice off sets some of those differences; e.g. a bike frame. On reflection maybe not enough though.
    Yes, to an extent. Again it all depends what you are measuring. Is it the difference between a light car against a heavy one, distance travelled for a given amount of fuel, or the whole lifecycle.
    It really comes down to how many miles are travelled in total.
    Posted By: GarethCWhat is is about processing aluminium that makes it so much more energy intensive than steel?
    It is harder to get aluminium out of the ground than steel. Higher melting points are something to do with it. I think that processing of aluminium can have lower energy costs i.e you can extrude it.
    Posted By: CWattersAs I recall epoxy resin is considered "probably a carcinogen".
    As were most of the chemicals used back then. I used to clean the tooling with toluene, liquid styrene and acetone. I am still waiting to see what happens.
   
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