The effect of relative humidity on output performance of inclined and automatic tracking solar power system

Abstract

The effect of relative humidity on the output performance of a solar power system using 70 Watts Multi-Silicon and 80 Watts Mono-Silicon Solar Modules that were set up independently in Port Harcourt (latitude 4⁰ 55’ 58” North and longitude 6⁰ 59’ 55” East), Rivers State, Nigeria (tropical climate region) was studied during the month of October and November in University of Port Harcourt environs. The set-up of 70 Watts solar panel was inclined stationary at 15⁰ for maximum solar reception while the set-up of 80 Watts solar panel had automatic solar tracker for effective capturing of solar radiation. For 70 Watts solar panel, the maximum power output of 59.99 Watt was obtained when the relative humidity was 30%. The minimum power of 0.00 watt was recorded when the relative humidity was 92%. There was 14.3% loss from maximum power output produced by 70 Watts solar module when compared with solar panel manufacturer’s power rating. For 80 Watts solar panel, the maximum output of 77.20 Watts was recorded when the relative humidity was 41% while minimum power output of 0.00 watts was recorded when the relative humidity was 100%. The percentage loss in power output of 80 Watts solar module was 3.5% when compared with the solar module manufacturer’s power rating. The results in both cases show inverse proportionality between solar panel’s power output and relative humidity. In addition, the use of automatic solar tracker effectively improved the efficiency of the solar power system in the environment (i.e. from 14.3% loss to 3.5% loss). Specifically, the efficiency of the power output of solar module in this environment was improved by approximately 11% when solar tracker was installed with solar power system.