A natural-gas-fired electrical power plant produces an output of 750 MW. By using a typical efficiency from Table 7.6 and neglecting the small amount of power drawn by the pump, calculate the rates at which:

(a) Heat is supplied to the water/steam in the steam generator.

(b) Waste heat is spent into the river adjacent to the power plant.

Table 7.6

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Energy System Required Input Desired Output Real Efficiency, n Engines and motors Internal-combustion Gasoline Crankshaft work 15–25% engine Diesel engine Diesel Crankshaft work 35-45% Electric motor Electricity Shaft work 80% Automobile Gasoline Motion 10-15% Electrical power generation Fossil-fuel plant Fuel Electricity 30-40% Fuel cells Fuel and oxidant Electricity 30-60% Nuclear plant Fuel Electricity 32-35% Photovoltaic solar cell Sunlight Electricity 5-15% Wind turbine Wind Shaft work 30-50% Wave energy convertor Waves and Electricity 10-20% currents Hydroelectric plant Water flow Electricity 70-90% Residential Forced-air furnace Natural gas Нeat 80-95% Hot water heater Natural gas Heat 60-65%