ABSTRACT
The U.S. Geological Survey has calculated that the heat energy in the upper 10 kilometers of the Earth’s crust in the U.S. is equal to over 600,000 times the country’s annual non-transportation energy consumption. Probably no more than a tiny fraction of this energy could ever be extracted economically. However, just one hundredth of 1% of the total is equal to half the country’s current non-transportation energy needs for more than a century, with only a fraction of the pollution from fossil-fueled energy sources.
