Quote:
Originally Posted by ConnClark
The efficiency of 33% is the efficiency of a typical Rankine cycle power plant (where most electricity is generated in the US).
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Not if you look at actual data. Yes, there are some older plants at about that level. Newer coal-fired plants are closer to 40%, while a combined-cycle gas turbine plant can be about 60% efficient (per Wikipedia:
Gas turbine - Wikipedia, the free encyclopedia )
Furthermore, since there is no way to know where any particular bit of electricity is coming from, you need to look at the whole grid. With 20% nuclear and maybe 10% hydro & other renewables, that boosts the overall grid efficiency (of fossil fuel -> electricity) to the 50% range.
Second, IC engines
as used in typical passenger vehicles aren't anywhere near 33% efficient, because they are almost always running far from their optimum BSFC.
Third, re lithium and "rare earths". Lithium is fairly common, and readily mined & recycled (far more so than petroleum!), and as someone has already stated, you need only a few pounds per vehicle, vs many tons of gasoline consumed over a vehicle lifetime. So-called rare earth elements actually aren't all that rare, either.
Just for interest, my Insight gets about 70 mpg. In 140K miles of driving, that's 2000 gallons of gasoline, about 6 tons. Since only about 30% of crude oil can be converted to gasoline, that's close to 20 tons of petroleum burned over a modest automotive lifetime.