As for the second part, I don't have time tonight to go over your figures, but I am very, very doubtful of them. You are going to manufacture, charge, and haul around a large, heavy battery made from exotic materials, and charge it using fossil fuel generated electricity delivered over a lossy transmission system, and achieve better efficiency than you get by burning the fuel directly? That's going to have to be one hell of an efficient electrical system. I don't believe it.
To save you a bit of time,
here is a link about the power grid. About halfway down the page:
Transmission and distribution losses in the USA were estimated at 7.2% in 1995. In general, losses are estimated from the discrepancy between energy produced (as reported by power plants) and energy sold to end customers; the difference between what is produced and what is consumed constitute transmission and distribution losses.
My estimate of 5% losses then wasn't all that far off. Changing that to 7.2% gives a final result of 40% instead of 41%. I'm 100% sure my other figures are correct, even pessimistic. I've seen figures of >90% charging efficiency and >95% motor efficiency but I went with 80% and 90%, respectively. That 60% figure for converting chemical energy in fossil fuel to electrical energy has been the ballpark for modern power plants
although many existing plants fall short of that.
Link ( see page 7 ) and note that 3412.14 BTU = 1 kWh . Natural gas power plants come in at 50% to 54% but efficiency improvements of NG power plants is expected to make them more efficient than 60% within a decade. Coal plants in the US average 10410 BTU/kWh, or roughly 33% efficient BUT a lot of the less efficient ones would be phased out/upgraded by the time large numbers of electric cars appear within the next decade. Figures for
state-of-the-art coal is about 7000 BTU/kWh ( 49% efficient ). You can probably approach 70% in both cases once efficient thermoelectrics are developed to recapture low-level waste heat. I'll also point out that in quite a few cases this so-called "waste heat" is actually utilized. NYC uses some of this waste heat for steam heating in Manhattan, for example.
OK, so even if we want to go with the lowest figures here, and assume 100% of power is generated at the lowest efficiency coal plant ( 33% ), we end up with a final figure of 0.33*0.928*0.8*0.9 = 22% instead of 40% ( note how this is
still much better than a petrol car ). However, if we do that, then in the interests of fairness we need to account for the energy used transporting, storing, and pumping the petrol directly burned in the internal combustion engine of the auto. These are parasitic losses in much the same way electrical transmission losses are. No idea of these figures offhand but I'd say a good ballpark estimate would be one-third of the energy contained in the fuel. So now your 15% best-case efficient petrol car goes to 10%, and your 30% best-case efficient diesel drops to 20%. Both figures are less than EVs running off of the worst-case coal plant. Besides, as I said, far from 100% of grid power is generated from fossil fuels anyway. Another thing to remember is even if cars could utilize the energy in fossil fuel
more efficiently than EVs using grid power, you still have the problem of emissions. EVs centralize emissions to a single, remote location where they can be more effectively controlled. Indeed, some prototype NG plants even sequester their CO2. You just can't do that burning the fuel in millions of small, often poorly tuned, internal combustion engines. I won't even get into the noise issues of ICE autos, either, other than to say that's another nail in their coffin.
And yes, hybrid is one of the most idiotic terms. Granted, it's technically correct as the powertrain is a hybrid of petrol and electric motors. However, the term has been so used/misused that the general public thinks the word hybrid always has energy-saving connectations. I've already had people ask me if LEDs could be considered hybrids because they save energy. :frusty:
.
