On Dec 11, 2007, at 6:13 AM, Terry Blanton wrote:
Not me. The energy used to make electricity: http://www.eia.doe.gov/emeu/aer/pdf/pages/sec8_3.pdf Out of 40 quads consumed to make electricity, only 13 quads makes it to the end user. Terry
It seems like something might be done to reclaim some of that lost heat. There may be some money to be made building bigger better cooling towers and also reclaiming stack heat, both methods using sterling engines to reclaim the heat. It is interesting that geothermal is about half as efficient as generator plants, which might be expected due to the low grade heat coming from geothermal. If waste power plant heat is about the same as geothermal, then it should be possible to reclaim at least 15 percent of it using sterling engines, or .15*29 quads = 4 quads. That is an increase of electric production of 30%, without burning any extra fuel. That's 1.17x10^12 kWh per year, which at $0.10/kWh is a 117 billion dollars a year potential revenue source. A company with that kind of revenue source trading at a P/E of 10 would be worth about a trillion bucks. Not bad.
The problem is making sure the heat recovery itself is economic. It would typically mean either replacing cooling towers or heat exchangers, or retrofitting to get sterlings into the heat flow. If land is available it might mean adding a cooling tower upstream of the existing one to take off some of the heat. This may not be very economic - which would be expected anyway because power companies would be doing it themselves. Cooling towers can be one of the most expensive components. Recovering 15% of the 70% waste heat is only about 10% of the total heat, but it represents a 30% increase in energy production, which is pretty good.
Horace Heffner http://www.mtaonline.net/~hheffner/
