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Old 05-04-2009, 09:22 PM   #131 (permalink)
RobertSmalls
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Quote:
Originally Posted by Jim Bullis View Post
What happened to the Ernie Rogers that argued for a 40% adjustment for the efficiency of the power plant that made the electricity?
Aw, jeez, I'm asleep at the wheel here. For every KJ of power that makes it to the grid, it takes an average of 2.5KJ of fuel.

Cost equivalence: 18.5KWh = 1 gal gasoline for me today. Wildly variable, changes daily, different everywhere.
Well to Wheels greenhouse gas equivalence: 15.2KWh = 1 gal gasoline
Energy equivalence of pure electricity: 34 KWh = 1 gal gasoline
Energy equivalence for grid average (guesstimated at 40% efficiency) plus 7.2% transmission losses: 12.6KWh = 1 gal.

I'm guesstimating 40% thermodynamic efficiency average, since most fossil-fueled plants get 36-40%, nuclear is slightly lower, and non-combustion methods could be said to be ~100% thermodynamically efficient for our purposes.

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