A power plant burns natural gas to generate 740 MW of electricity with 42% efficiency. 88%...

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A power plant burns natural gas to generate 740 MW of electricity with 42% efficiency. 88% of the waste heat is removed by cooling water. The natural gas has a heat content of 49,000 kJ/kg. a. How many tons of natural gas does this plant burn per day? b. Suppose the cooling water is taken from and returned to a river with a flow of 18 m³/s and an upstream temperature of 16 °C. What is the river temperature downstream of the power plant? c. Alternatively, the heat removed by cooling water can be removed by evaporating water rather than returning it to the river. If water is vaporized at a temperature of 50 °C, calculate the volumetric rate of loss of water to the atmosphere, in m³/s, needed to cool the plant. Find and use constants appropriate to this temperature. A power plant burns natural gas to generate 740 MW of electricity with 42% efficiency. 88% of the waste heat is removed by cooling water. The natural gas has a heat content of 49,000 kJ/kg. a. How many tons of natural gas does this plant burn per day? b. Suppose the cooling water is taken from and returned to a river with a flow of 18 m³/s and an upstream temperature of 16 °C. What is the river temperature downstream of the power plant? c. Alternatively, the heat removed by cooling water can be removed by evaporating water rather than returning it to the river. If water is vaporized at a temperature of 50 °C, calculate the volumetric rate of loss of water to the atmosphere, in m³/s, needed to cool the plant. Find and use constants appropriate to this temperature.