Question

A typical coal-fired power plant burns 260 metric tons of coal every hour to generate 2.6×10⁶ MJ of electricity. 1 metric ton = 1000 kg; 1 metric ton of coal has a volume of 1.5 m3. The heat of combustion is 28 MJ/kg. Assume that all heat is transferred from the fuel to the boiler and that all the work done in spinning the turbine is transformed into electrical energy.

Part A: Suppose the coal is piled up in a 12 m × 14 m room. How tall must the pile be to operate the plant for one day?

Express your answer in meters.

Part B: What is the power plant's thermal efficiency?

Express your answer as a percentage.

Answer 1