Question

Consider a heat engine operating between Earth's surface, at a typical temperature of 295 K, and the bottom of a geothermal well 1.0 km deep. Given a geothermal gradient of 25 degrees C/km, what would be the maximum possible efficiency of such a heat engine?With your answer to the previous question, if we could tap the geothermal flow over 10 percent of the earth's land area (excluding the oceans) with such heat engines, roughly what percentage of humankind's 16 TW energy usage could we supply? Take the earth's land area as 150.0E6 kilometers-squared.

Answer 1