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Old 07-09-2010, 02:51 PM   #7 (permalink)
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Originally Posted by dcb View Post
There was a note in the DOE paper, and I'm not sure of the entirety of its scope, but they skipped all non-fossil fuel sources in their analysis?
Comment 7: The U.S. Average
Electricity Generation factor (Tg = 0.328)
is based only on fossil fuel generation,

But that leaves out like almost 1/3 of the grid, at least as of 2009
(I'm rooting for the renewable section and gladly give my local windfarm a couple extra bucks)
I am also rooting for renewables, but we're still around 70% fossil-fueled. Those power plants have a service life of over fourty years, so they'll be with us for a looong time.

Regarding "The U.S. Average
Electricity Generation factor (Tg = 0.328)
is based only on fossil fuel generation". Efficiency of nuclear is around 30%. But how do you measure efficiency of hydro, solar, and wind? PV panels catch perhaps 8% of the sunlight hitting them, and windmills catch only a tiny fraction of the kinetic energy passing their swept area. But you can call them 100% efficient, because if the hydro dam weren't there, then zero percent of the energy would have been captured.

So if you want to use 14.8KWh/gal by an energy-equivalence method, that sounds fine with me.
Originally Posted by comptiger5000 View Post
Even if an EV emits the same amount of pollution per mile as an ICE car, it's still beneficial, as they're often cheaper to run, and their pollution can be lowered without replacing the vehicle, as the power grid changes over time.
There are pros and cons to EVs aside from the MPGe and total cost of ownership. Lots of those ended up being discussed here. My favorite pro: it's fun to play with electric drive. Converting a car to PHEV or EV can be a rewarding hobby. The issue of CO2 is separate.


Unfortunately, the extra battery weight (and resultant extra structural and motor weight), and the added inefficiency of the battery and charger shifts the electric vehicle to parity with a conventional vehicle, and behind a hybrid.

There's a very cool sensitivity analysis on page seven here: , and a few other corroborating studies I can't put my fingers on right now.
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