Problem # p020

Carnot Efficiency

From a geothermal underground source saturated water vapor is extracted with a temperature of 200°C.

  1. What is the maximum thermal efficiency (= ratio of benefits to costs) of a cyclic heat engine which uses the water vapor as heat source and expells its "waste" heat to a 20 oC cold reservoir ?

  2. How much steam per second do we need at this efficiency for a 1 MW power plant if we extract 1930 kJ of heat from each kilogram of water vapor to feed into the cyclic heat engine?