Authors : O. O., Mong; O. C., Nwufo; G. N., Nwaji; A. C., Okoronkwo; E. E. Anyanwu

Volume/Issue : Volume 11 - 2026, Issue 3 - March

Google Scholar : https://tinyurl.com/yck9c75c

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DOI : https://doi.org/10.38124/ijisrt/26mar1323

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Abstract : This study presents the design of a solar photovoltaic (PV) power system designed from the first principle to power a 1 kW Sub-Wet Bulb Evaporative Cooling (SWEC) system for building comfort applications in Owerri, Nigeria. A cooling load of a pilot office space was estimated following ASHRAE standards, yielding a design cooling load of 0.978 kW (approximately 0.3 tons of refrigeration) at 8-hour daily operation. This load informed the sizing of SWEC components at a heat exchanger area of 1.4 m² and a total electrical load of 303 W comprising fan, pump, and data logger/ control system. The solar photovoltaic (PV) power system sizing were carried out considering system losses, depth of discharge, 8-hour noontime sunlight of Owerri, Nigeria. The results show that a 400 W solar array with a battery bank of 303 Ah at 12 V, configured as two 150 Ah batteries in parallel effectively powered the system, at an energy yield of over 7% more than the power needed to power the cooling system. The result demonstrated the viability of solar-powered evaporative cooling system for sustainable building applications.

Keywords : Sub-Wet Bulb Evaporative Cooling, Solar Photovoltaic System, Cooling Load Estimation, Sustainable Cooling.

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