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Subject:  Re: Electric car monies Date:  2/5/2013  1:30 PM
Author:  waterfell Number:  40648 of 90628

The best super heated steam power plants are hitting in excess of 90 percent.

That is news to me. The most efficient steam plants I am familiar with are the new combined cycle gas plants. They can achieve 60% thermal efficiency, but it takes a gas turbine and a steam turbine all in one power plant to get that sort of efficiency. A Carnot efficiency of 90% would require a steam inlet temperature of over 4000 degrees F. That is way too high for today's power plants.

Empirically, no heat engine has ever been shown to run at a greater efficiency than a Carnot cycle heat engine.

The point remains, though, that power plants are generally more efficient than internal combustion engines. So an electric car running on electricity from a fossil-fueled power plant still produces less CO2 per mile than a standard ICE car. The CO2 emissions can be eliminated completely if the power plant runs on uranium. But that concept is unpopular amongst the environmental crowd.

- Pete
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