Suppose an old power plant uses steam turbines to produce 0.5 GW (5 x 10° W) of electricity. The turbines take in steam at a temperature of 600°C, and waste heat is expelled into the environment at 30°C. (a) If the plant operates at its maximum efficiency, at what rate does it expel its waste heat into the environment? Assume the cold reservoir for this plant is a river whose flow rate is 80 m³/s. By how much will (b) the temperature of the river increase due to the waste heat expelled by the plant? (c) environment), the plant could instead be cooled by evaporating river water. At what rate would the To avoid increasing the temperature of the river water (which may be harmful to the water have to be evaporated to cool the plant, assuming the latent heat to evaporate water at the relevant temperature is 2400 J/g?

Suppose an old power plant uses steam turbines to produce 0.5 GW (5 x 10° W) of electricity. The turbines take in steam at a temperature of 600°C, and waste heat is expelled into the environment at 30°C. (a) If the plant operates at its maximum efficiency, at what rate does it expel its waste heat into the environment? Assume the cold reservoir for this plant is a river whose flow rate is 80 m³/s. By how much will (b) the temperature of the river increase due to the waste heat expelled by the plant? (c) environment), the plant could instead be cooled by evaporating river water. At what rate would the To avoid increasing the temperature of the river water (which may be harmful to the water have to be evaporated to cool the plant, assuming the latent heat to evaporate water at the relevant temperature is 2400 J/g?

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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