Sustainable Energy
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Sustainable Energy. 2014, 2(1), 29-34
DOI: 10.12691/rse-2-1-6
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Simplified Method for Night Sky Radiation Analysis in a Cool-Pool System

Alibakhsh Kasaeian1, , Mohammad Sameti1 and Amin Toghi Eshghi1

1Department of Renewable Energies, Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran

Pub. Date: February 06, 2014

Cite this paper:
Alibakhsh Kasaeian, Mohammad Sameti and Amin Toghi Eshghi. Simplified Method for Night Sky Radiation Analysis in a Cool-Pool System. Sustainable Energy. 2014; 2(1):29-34. doi: 10.12691/rse-2-1-6


The conventional mechanical building cooling systems are energy demanding equipment. Needing for low-energy consumption systems is a motivation for utilizing ambient energy resources such as ground, ambient air, sky and water as alternative resources. Night sky can be a good candidate as a heat sink to be used in cooling systems. The present study proposes and presents a simplified method for computing net outgoing energy exchanged between night sky and a cool-pool in a building cooling system. Considering a real night condition with a 3 m × 4 m pool and overall energy conversion efficiency of 75%, we obtained that the aforementioned system can replace a 4000 watts swamp cooler works for 6 hours a day.

building passive cooling night sky radiation cooling cool-pool

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