Home  5  Books  5  GBEzine  5  News  5  HelpDesk  5  Register  5  GreenBuilding.co.uk
Not signed in (Sign In)

Categories



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.

Buy individually or both books together. Delivery is free!


powered by Surfing Waves




Vanilla 1.0.3 is a product of Lussumo. More Information: Documentation, Community Support.

Welcome to new Forum Visitors
Join the forum now and benefit from discussions with thousands of other green building fans and discounts on Green Building Press publications: Apply now.




    • CommentAuthortorrent99
    • CommentTimeFeb 16th 2017
     
    But the EV does have the OPTION of getting its energy from non-oil sources.
    The IC engine does not.


    BTW has anyone done any analysis on the overall efficiency boost of Hybrid vehicles?
    Obviously regenerative braking is a positive, but the weight and losses of the system is a negative....
    • CommentAuthorringi
    • CommentTimeFeb 16th 2017
     
    => Modern oil using transport engines are remarkably efficient

    Not when they are cold, or in stop/go tragic etc.....

    Also the point is that once we have enough EV connected to the grid, we can use 100% of the wind power we get overnight, therefore wind power becomes a lot more worthwhile to install. We need something like engine drive generators for when we get a few weeks without wind every few years.
    • CommentAuthorEd Davies
    • CommentTimeFeb 16th 2017
     
    Posted By:billtIf you wanted to electrify all road transport you'ld need a lot more than that.

    According to https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/573269/ECUK_November_2016.pdf the UK used 40,521 ktoe (kilo tonnes oil equivalent) for road transport in 2015. That converts to 471,260 GWhr or 54GW of generating capacity running continuously.
    But IC road vehicles throw a third of their energy out of the exhaust and another third through the radiator so to replace the actually useful third you'd only need 54/3 = 18 GW. If that's for all road vehicles then it seems very much in line with 12.5 GW for electric cars.
    • CommentAuthorbillt
    • CommentTimeFeb 16th 2017
     
    You are making the assumption that electric vehicles are 100% efficient, which is not the case. Difficult to know what the efficiencies actually are, but a fair guess for AC input to useful power out is likely to be 70-80%. (Best case motor efficiency 90%, battery efficiency 90% then you've got mechanical losses as well.) On top of that you have grid losses of about 8% so that's dropped your EV efficiency down to 65% or less. That puts your 18GW guess up to a 36GW guess, much more than the grid can provide in its present state without stopping supply for any other use. Never going to happen with renewables, for political reasons if nothing else.

    Of course the grid is still fed mainly by stuff being burnt (60% at the moment) at an efficiency of about 35% so we're now down to 20% system efficiency, oh dear, the oil fueled vehicle doesn't look so bad!

    And we are still nowhere near solving the EV range problem, or the price problem.
    •  
      CommentAuthordjh
    • CommentTimeFeb 16th 2017 edited
     
    Posted By: torrent99But the EV does have the OPTION of getting its energy from non-oil sources.
    The IC engine does not.

    It does. In fact it is mandatory in the US and also I think in Europe that a fraction of the fuel is derived from biomass. There's nothing to stop usable transport fuels being synthesized from non-oil sources, it's just not economically attractive at present.
    • CommentAuthorEd Davies
    • CommentTimeFeb 16th 2017
     
    Billt, yes, it could be as much as 36 GW total though I really doubt 54 GW. We're agreeing really, it's a significant amount of generation that'd be needed. EVs aren't a get out of jail free card.
    • CommentAuthorSprocket
    • CommentTimeFeb 17th 2017
     
    This arrived in my inbox.

    https://www.elektormagazine.com/news/80-price-drop-in-ev-batteries

    Interesting points raised in that v.short article:-

    The cost of battery packs for electric vehicles has fallen nearly 80% since 2010.

    BP predicts there’ll be a 100 million EVs on the road in 2035, constituting a 6% market share in road transport. The International Energy Agency is slightly more optimistic with a projection of between 100 and 140 million EVs in 2030.

    A new study by the Carbon Tracker Initiative has a far more positive outlook on the speed of EV market penetration. It predicts EVs will reach price parity with ICE vehicles as soon as 2020. Between then and 2030 electric driving will take 19-21% of the market share.
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 17th 2017
     
    The price of gasoline has dropped by 50% since 2012.
    And that delivers nearly 13 kWh/kg and costs about $2 a kg.

    We really need to keep things in perspective.
    • CommentAuthorSprocket
    • CommentTimeFeb 17th 2017
     
    But that's cost of the energy source - not relevant to battery specs or price. Once the car purchase cost is at parity or better then surely you should be comparing the cost of running electricity vs cost of gasoline.

    And on cost per mile, surely electricity is currently a clear winner:-

    https://avt.inl.gov/sites/default/files/pdf/fsev/costs.pdf
    • CommentAuthorSprocket
    • CommentTimeFeb 17th 2017
     
    Hmmm... not so clear if you buy your electricity from charging points whilst out and about though. It seems those prices are all over the place, even costing more than petrol in many cases.
    • CommentAuthorwookey
    • CommentTimeFeb 17th 2017
     
    Here's a useful take on how much extra generation is required:
    https://energy-surprises.blogspot.co.uk/2017/02/what-difference-will-electric-cars-make.html
    (none at all for the first 10 million vehicles).
    • CommentAuthorbillt
    • CommentTimeFeb 17th 2017
     
    Posted By: SprocketBut that's cost of the energy source - not relevant to battery specs or price. Once the car purchase cost is at parity or better then surely you should be comparing the cost of running electricity vs cost of gasoline.

    And on cost per mile, surely electricity is currently a clear winner:-

    https://avt.inl.gov/sites/default/files/pdf/fsev/costs.pdf


    It's only a winner because of lots of subsidies, primarily no duty on the fuel. Using that chart a good EV does 4m/kwh that's 3 p per mile. If you take out the duty element of diesel fuel it's about 60p per litre, with my car that's about 4p per mile, less on a long run. Neither pay VED. (I suspect 4 miles per kWh is optimistic for an electric car.)

    Of course the main cost of any car (unless you buy bangers for a few hundred quid) is depreciation and EVs are absolutely awful for that, so total cost of ownership of an EV is likely to be much worse than a for an IC car. They are still massively over priced. An unsubsidised Nissan Leaf is of the order of £30,000 to buy new, about twice the price of an equivalent sized, but more versatile IC car.
    • CommentAuthorbillt
    • CommentTimeFeb 17th 2017
     
    Posted By: wookeyHere's a useful take on how much extra generation is required:
    https://energy-surprises.blogspot.co.uk/2017/02/what-difference-will-electric-cars-make.html
    (none at all for the first 10 million vehicles).


    Quite likely, but that's because the grid has a good degree of elasticity and can increase output according to demand to some extent. The more renewables contribute the less the flexibility.
    • CommentAuthorEd Davies
    • CommentTimeFeb 17th 2017
     
    Posted By: SprocketBP predicts there’ll be a 100 million EVs on the road in 2035, constituting a 6% market share in road transport. The International Energy Agency is slightly more optimistic with a projection of between 100 and 140 million EVs in 2030.
    Both BP and the IEA are notorious for under-estimating renewable growth and price reductions.
    •  
      CommentAuthordjh
    • CommentTimeFeb 17th 2017
     
    I thought those figures sounded more likely as an estimate of the number of autonomous cars, but even then unduly pessimistic.
    • CommentAuthorringi
    • CommentTimeFeb 17th 2017
     
    Posted By: billtThe more renewables contribute the less the flexibility.


    The move EV that are left plug in for many hours, the more controllable demand there is..... Even better for a plug in hybrid that could go without a charge if the price of charging was too high on a given night.
    • CommentAuthorEd Davies
    • CommentTimeFeb 17th 2017
     
    I'd have thought it'd be space heating and DHW, etc, which will eat into the yellow bit of the graph in the which Wookey references (the currently unused generation off peak) as we move to electrify things which will reduce the amount available for EVs.
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 18th 2017 edited
     
    Posted By: SprocketBut that's cost of the energy source - not relevant to battery specs or price
    Depends how you view a battery. Is it just a container for the energy, like a fuel tank (I have changed 2 in 30+ years of motoring, both cheap <£100 each).
    Or do you view the batteries as something different?
    • CommentAuthorbillt
    • CommentTimeFeb 18th 2017
     
    Posted By: ringiThe move EV that are left plug in for many hours, the more controllable demand there is..... Even better for a plug in hybrid that could go without a charge if the price of charging was too high on a given night.


    How do you work that out? At the moment there is no demand control on EVs. You plug them in and they consume all the power that they can cope with. A suitable system to cope with demand management is decades away once it has been decided on and designed. Haven't seen any real signs of that happening, apart from largely imaginary schemes.

    Going back to running costs, if you're foolish enough to lease a battery the battery costs are eye-watering. https://www.renault.co.uk/renault-finance/battery-hire.html over 13p/mile for <4,500 miles p.a. down to a mere > 10.2p/mile for <10,500 miles p.a. Those are the cheap rates.
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 18th 2017
     
    Who buys EV's?
    Is it companies, local authorities, private buyers, pensioners, low medium or high mileage users, two car families, 'eco' warriors, high income of medium income families, rural or urban
    The demographics will make a lot of difference to the time of usage.
    •  
      CommentAuthorfostertom
    • CommentTimeFeb 19th 2017
     
    Posted By: SteamyTeaThe price of gasoline has dropped by 50% since 2012
    To the fuel cos yes, but not passed on to pump prices! It's bounced between £1.05 to £1.35 per litre.
    • CommentAuthorbillt
    • CommentTimeFeb 19th 2017
     
    See above, a significant part of the retail price is a fixed amount of duty.

    Take the duty out (57.95 pence) and that range becomes £0.24 - £0.65. (Without VAT it would be £0.21 - £0.55.
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 19th 2017
     
    Say it was 40p/litre, that would be about 4p/kWh
    My car does about 45 MPG, so that is 1 kWh/mile, so fuel cost only is 4p/mile if we strip out tax.
    An EV will use about 3 miles on a kWh, a kWh is about 13p without tax in the UK, so about the same price.

    If the world, not the UK only, is serious abut getting ICE vehicles off the roads, then the easy way is to increase fuel taxes to the UK level.
    • CommentAuthorringi
    • CommentTimeFeb 19th 2017
     
    Posted By: SteamyTeaAn EV will use about 3 miles on a kWh, a kWh is about 13p without tax in the UK, so about the same price.


    If charging at night on E7, it is close to 7p per kWh.

    Posted By: billtHow do you work that out? At the moment there is no demand control on EVs. You plug them in and they consume all the power that they can cope with. A suitable system to cope with demand management is decades away once it has been decided on and designed. Haven't seen any real signs of that happening, apart from largely imaginary schemes.


    I far as I know most EV owners charge them on E7, this moves the demand from EV to outside of the peak demand times. Smart meter enable providers to offer tariffs with more than two bands etc without having to change the meters their customers have.

    The boxes that EV plug into (assuming more than 2KW charging) tell the car how much power it can take, the cars can already tell the boxes how much charge it needs. These boxes could easily connect to the internet over WiFi to be told the half hour rates for the next day. Likewise the car can be made to connect to WiFi. Also most EVs have updateable software.

    Smart meter allows a provider to prove their customers use electric power at better times then the average person, hence allowing the provider to pay lower balancing charges etc. A provider can also tell who out of their customers used power at the best time. Therefore it would be easy for a provider to provide a £10 cash back each month to all of their customers that had a better demand profile then the average user.

    I expect that as soon we start to use usage at E7 time’s increasing to be an issue, the power providers will act quickly, by then close to 100% of people will have smart meters. Until that time, power will remain so cheap at E7 times that there are few incentives for a EV owner to charge in other ways.
    • CommentAuthorbillt
    • CommentTimeFeb 19th 2017
     
    So there is no system to do this automatically at the moment, nor any such system planned in the near future, just a lot of fantasy ifs and maybes.

    Yes, it is theoretically possible to remotely control EV charging according to grid availability, but such a system doesn't exist yet and there is no likelihood of it happening any time soon.

    EV users charging at economy rates has nothing at all with minimising emissions, but rather a lot to do with minimising the users costs. It's just another distortion of costs in favour of EV owners.
    •  
      CommentAuthorDamonHD
    • CommentTimeFeb 19th 2017
     
    "V2G" has been worked on for a while, in a number of places around the world. It is not vapourware.

    Moving demand (for charging) away from peaks does keep infrastructure and wholesale energy costs down, and reduces the need (for example) for 'dirty' generation from rarely used emergency generation plant.

    As Ed has said elsewhere one can argue about whether, for example, instantaneous carbon intensity is 'real', but flattening the demand curve, or better, matching it to the available of intermittent generation, is a real benefit.

    Rgds

    Damon
    •  
      CommentAuthordjh
    • CommentTimeFeb 19th 2017
     
    Posted By: billtEV users charging at economy rates has nothing at all with minimising emissions, but rather a lot to do with minimising the users costs. It's just another distortion of costs in favour of EV owners.

    E7 rates have nothing at all to do with favouring EV owners. EV owners using E7 charging are a fortunate coincidence of interests; the grid benefits and the car owners benefit. So it happens.

    I don't see the same happy circumstances surrounding Vehicle-To-Grid (V2G). Why would an EV owner voluntarily put their battery through extra charge-discharge cycles, reducing its lifetime, unless incentivised?

    PS People are notoriously bad at guessing future timescales. It helps to break developments down into stages and estimate what is required for each stage.
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 19th 2017
     
    Posted By: DamonHD"V2G" has been worked on for a while, in a number of places around the world. It is not vapourware.
    Yes, but it is not being implemented and is mostly of academic interest, and the UK can't agree on how to fit smart metering, so it is a while off.
    Nice to see you on here again.
    Posted By: ringiIf charging at night on E7, it is close to 7p per kWh.
    Think mine is closer to 9p/kWh now, they have just put the price up. From the reading I did a while back, it seems most people plug in when they get home, which is the time of highest demand.

    I think that at the moment, and for the foreseeable future, there is no economic case for the general public to choose an EV over an ICE (small cars like the Yaris are phenomenal on fuel). I filled up tonight, did a trip to St. Ives, total distance of about 30 miles, and the fuel usage is showing 56 MPG (and anyone knows St. Ives will know that it is not an easy run in or out, is hilly and slow). And that is from a ten year old Ford C-Max.
    • CommentAuthorringi
    • CommentTimeFeb 20th 2017
     
    Posted By: djhI don't see the same happy circumstances surrounding Vehicle-To-Grid (V2G). Why would an EV owner voluntarily put their battery through extra charge-discharge cycles, reducing its lifetime, unless incentivised?


    Posted By: SteamyTeait seems most people plug in when they get home, which is the time of highest demand.


    There is at least one provider that is charging more for electric in the evening peak in exchange for a lower cost for the rest of the day time...... It needs a critical mass before the products come on the market to make it easy for people to sift demand, when the times comes, things could move very quickly.

    We tent to overestimate what we change in the in the short term and underestimate what will in the long term.
    •  
      CommentAuthorSteamyTea
    • CommentTimeFeb 20th 2017 edited
     
    Posted By: ringioverestimate what we change in the in the short term and underestimate what will in the long term.
    This seems to be true on the face of it.
    Take personal computing, which is now about 30 years old. Taken 30 years to go from basically no general population understanding of it, to invading everything we do.
    In that same 30 year, we have gone from a Ford Escort to a Ford Focus, basically the same thing, improved yes, but not unrecognisable in form or function.
    There is a big risk in assuming that anything with wires on it will be life changing and will develop at the same pace as personal computing has.

    And that is all before we start planning and building new power generation. So add on another 30 years for that.
   
The Ecobuilding Buzz
Site Map    |   Home    |   View Cart    |   Pressroom   |   Business   |   Links   
Logout    

© Green Building Press