25. A solar-power-tower plant is considered for a given city with a DNI = 2072 kWh/m2.year. Heliostats with a total area of 80,000 m² are to be used to reflect solar radiation into a receiver. When the average solar irradiation is 950 (W/m), steam is produced at a rate of 20 kg/s. The resulting steam is directed to a turbine to produce mechanical power. A generator is connected to turbine to convert turbine shaft power into electricity. Assume the collector-receiver conversion is 85 percent efficient; take the average thermal efficiency to be 18 percent, and the generator efficiency to be 96 percent. (a) How much electricity can be produced per year? What is the temperature of the produced steam if the fluid initial temperature is 25'C, and the specific heat capacity is 4.2 kJ/kg."C?

25. A solar-power-tower plant is considered for a given city with a DNI = 2072 kWh/m2.year. Heliostats with a total area of 80,000 m² are to be used to reflect solar radiation into a receiver. When the average solar irradiation is 950 (W/m), steam is produced at a rate of 20 kg/s. The resulting steam is directed to a turbine to produce mechanical power. A generator is connected to turbine to convert turbine shaft power into electricity. Assume the collector-receiver conversion is 85 percent efficient; take the average thermal efficiency to be 18 percent, and the generator efficiency to be 96 percent. (a) How much electricity can be produced per year? What is the temperature of the produced steam if the fluid initial temperature is 25'C, and the specific heat capacity is 4.2 kJ/kg."C?

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter8: Natural Convection

Section: Chapter Questions

Problem 8.44P

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