a) A coal-burning power plant produces 1500 MW of power with an efficiency of 0.3. Given that 20% of the waste heat is released to the air via the stack gases, at what rate do they need to withdraw water from the ocean to discharge the remaining waste heat if they are limited to a 5°C increase in water temperature? Answer: 133.8 m³/s b) Recognizing that this is an excessive volume of plankton-rich water, new regulations focus on the withdrawal rate and limit it to 1000 MGD. What would be the temperature increase of the thermal discharge in this case? Answer: 15.28°C c) If both regulations are applied, the power company will have to reduce power production to continue operating. Assuming they continue to discharge 80% of their waste heat through cooling waters, how much electric power could they produce with temperature increase limited to 5°C and withdrawal rate limited to 1000 MGD? Answer: 491 MW

a) A coal-burning power plant produces 1500 MW of power with an efficiency of 0.3. Given that 20% of the waste heat is released to the air via the stack gases, at what rate do they need to withdraw water from the ocean to discharge the remaining waste heat if they are limited to a 5°C increase in water temperature? Answer: 133.8 m³/s b) Recognizing that this is an excessive volume of plankton-rich water, new regulations focus on the withdrawal rate and limit it to 1000 MGD. What would be the temperature increase of the thermal discharge in this case? Answer: 15.28°C c) If both regulations are applied, the power company will have to reduce power production to continue operating. Assuming they continue to discharge 80% of their waste heat through cooling waters, how much electric power could they produce with temperature increase limited to 5°C and withdrawal rate limited to 1000 MGD? Answer: 491 MW

Sustainable Energy

2nd Edition

ISBN:9781337551663

Author:DUNLAP, Richard A.

Publisher:DUNLAP, Richard A.

Chapter14: Ocean Thermal Energy Conversion And Ocean Salinity Gradient Energy

Section: Chapter Questions

Problem 10P

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