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bearing in mind the new Blackpool gas field
BTW, I see Tesla has reported to the SEC (Securities Exchange Commission) that they don't plan to make a profit in the foreseeable future! Sounds like a pretty safe investment to me.
Electric (BEV) from natural-gas:NG fired power station(65%) + transmission losses ~ 55% of fuel energy recovered.+ Charger conversion losses ~ 48%+ Pwr controller/motor losses ~ 40%On-board natural-gas:A purpose-built engine using NG can achieve higher compression-ratios than petrol, so a hybrid NG-powered vehicle could conceivably reach high forties overall (might be a little lower with drivetrain losses) - Say ~46%.
The gasoline engine was only about 30% efficient, plus some other related engine losses including the water pump dropping it down to about 25% efficiency.
I'm not sure how much difference it will make in the end, but don't you also need to include a piece of the the CO2 released in constructing the power generation and distribution systems, or would that depend on whether one was biased for or against EVs? 
There is also a CO2 cost to liquify gas for fuel & an additional cost for distribution.If I recall correctly there is also an issue with CH4 in 2 & 4 stroke engines - CH4 is harder to compress than more complex (liquid) hydrocarbon fuels - thus reducing engine efficeincy This could be overcome by using turbines...
The compression issue with CH4 is a new one on me. Most of the stuff being compressed is nitrogen and oxygen, so I don't understand what difference it would make.
Quote from: Geezer on 28/10/2011 19:40:03The compression issue with CH4 is a new one on me. Most of the stuff being compressed is nitrogen and oxygen, so I don't understand what difference it would make.Unless you wish to tether your car to your stove outlet with a long hose, you will have to transport Natural Gas as either CNG (compressed Natural Gas) or LNG (Liquid Natural Gas). Which means at some point the fuel needs to be compressed.Gasoline, on the other hand, doesn't need to be compressed for transport.Ocean Tankers, and presumably railcars and tanker trucks all carry LNG.I have no idea what central distribution pipelines carry.Your home delivery lines are all at low pressure.Anyway, so the repressurizing of the Natural Gas may or may not be an issue (with the original distribution mode being equal for electricity generation or vehicle use).
True. If it's already liquefied, why not inject it into the engine in liquid form?
Quote from: Geezer on 29/10/2011 00:26:02True. If it's already liquefied, why not inject it into the engine in liquid form?I was talking about transport (in vehicles).However, you could run something like common-rail injection without requiring an injection pump.
Quote from: CliffordK on 29/10/2011 09:15:45Quote from: Geezer on 29/10/2011 00:26:02True. If it's already liquefied, why not inject it into the engine in liquid form?I was talking about transport (in vehicles).However, you could run something like common-rail injection without requiring an injection pump.This could cool the charge quite considerably couldn't it?This has both potentially good and bad effects.It would indeed be naturally suited to a late-in-the-compression-stroke injection strategy though.As Geezer says I can't see how the gaseous-fuel content (what: 5% by mass?) of the charge would make any noticable difference in the compressive work needed (in the cylider that is), even if the CH4 was pre-injected at ambient P & T.
The other answer is that in the UK you can pay for your electricity to be produced (on average) entirely using wind, so an electric car has zero carbon footprint.
If, say 5% of the power is generated by wind, and 95% by other sources. Then, if 4% of the people pay for "pure wind power"...Then they get 100% "wind power".Everyone else gets 1% Wind power, and 99% Other.
And, on a calm, windless day... are those people buying the wind power accepting a brown-out?
I certainly don't want the government to start discharging my EV car without my permission.
Quote from: CliffordK on 01/02/2012 23:49:28I certainly don't want the government to start discharging my EV car without my permission. It would not be without your permission. There would have to be a system that allowed you to set a price for the energy you supplied. At a certain price, you would be happy to sell it!
However, if the power company offers $1 per discharge cycle on my batteries.And the battery pack is valued between $3,000 and $20,000.
The situation is that the power company is desperate for electricity, if they paid $0.2 per kWh nobody would build peaker plants, and nobody would give them any juice!