Comments on: Nearly 200 Gigawatts of US Energy is Wasted http://cleantechnica.com/2010/08/09/nearly-200-gigawatts-of-us-energy-is-wasted/ Clean Tech News & Views: Solar Energy News. Wind Energy News. EV News. & More. Mon, 29 Dec 2014 10:14:00 +0000 hourly 1 http://wordpress.org/?v=4.0.1 By: Mark http://cleantechnica.com/2010/08/09/nearly-200-gigawatts-of-us-energy-is-wasted/#comment-11371 Thu, 19 Aug 2010 10:21:14 +0000 http://cleantechnica.com/?p=13895#comment-11371 “Coal-fired power plants lose as much as 51% of their energy in conversion loss… Nuclear plants waste 21%.”

These figures refer to percentage of generating source rather than heat loss for each of the sources.

]]> By: Peter Wilson http://cleantechnica.com/2010/08/09/nearly-200-gigawatts-of-us-energy-is-wasted/#comment-11370 Fri, 13 Aug 2010 03:25:15 +0000 http://cleantechnica.com/?p=13895#comment-11370 Sounds all well and good but you need to do a bit of reading on entropy and exergy to understand why so much heat is “wasted” The quality of this energy and the heat difference you have available to extract useful work from this energy is very low.

As for saying little research has been done since the 1950’s that is plain wrong. Power companies have spent a lot of money extracting energy from the coal and oil they burn in order to reduce costs, bump profits and executive salaries. The materials they use, the pressures they now operate at and the fuel burners they use are all a result of research over many years.

PJW

]]> By: Bill Hewitt http://cleantechnica.com/2010/08/09/nearly-200-gigawatts-of-us-energy-is-wasted/#comment-11369 Fri, 13 Aug 2010 00:05:08 +0000 http://cleantechnica.com/?p=13895#comment-11369 The numbers are a little off here. Conventional thermal power plants – be they coal, gas or nuclear powered – routinely all waste upwards of 60% of the energy put in as heat. That’s this flow chart: http://www.eia.doe.gov/emeu/aer/diagram5.html A few percentage points are lost in transmission and distribution as well.

Coal provides about half of the electricity in the U.S., gas 17%, nukes about 20%, and renewables about 9%. (That last percentage is rapidly increasing.) See this chart to illustrate how energy is generated and consumed. http://www.eia.doe.gov/emeu/aer/pecss_diagram.html

The important point remains, as your post notes: we can do a tremendous amount with the energy we throw away at these plants. Tom and Sean Casten are, of course, visionaries in this regard. At the end of the day, though, we want to be using “micropower” – renewable energy, generated locally, with massive amounts of cogeneration in play. We’re getting there.

]]> By: Jack http://cleantechnica.com/2010/08/09/nearly-200-gigawatts-of-us-energy-is-wasted/#comment-11368 Tue, 10 Aug 2010 14:56:24 +0000 http://cleantechnica.com/?p=13895#comment-11368 They make a product here in the USA to recycle waste heat to electricity.

http://www.ener-g-rotors.com

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