Impact of high temperature on PV productivity in hot desert climates

Abstract

Hot dry climate regions enjoy high solar irradiation, albeit with high ambient temperatures. These two factors have a contradictory effect on the power generated from PV systems. This work studies the combined effect of high ambient temperature and high irradiation on the net performance of PV systems. The study is based on monitoring a grid-connected 5 kW PV system installed on the rooftop of the Energy Research Center of the University of Khartoum, Sudan. The performance was monitored by meteorological and power measurement equipment from April 2017 to March 2018. The results showed stable power output from the PV system with an average final yield of 4.57 kWh/kWp and a 0.21 standard deviation from this average value. The stability in power output is due to the compensation of the efficiency degradation due to high temperature by high irradiation in summer. This is combined with the relatively low irradiation in winter compensated by the low temperature effect in winter. The annual deviation of the temperature and irradiation is small in Khartoum due to its proximity to the equator. The semi desert climate, offers Khartoum notably few annual cloudy hours. These characteristics were compared with the annual performance of other countries with different climates. The conclusion from this work on hot dry regions is that despite the negative effect of temperature, the annual output power from the system tends to be stable due to the substitution contributed by the regionally high radiation and the relatively cool winter climate.

Assessing the combined effects of local climate and mounting configuration on the electrical and thermal performance of photovoltaic systems. Application to the greater Sydney area

“…The primary objective of this study is to investigate the thermal and electrical performance of PV systems, assessing the influence of Sydney urban overheating and mounting configurations, with a specific focus on periods of exceptionally high temperatures during the summer periods. It is worth noting that while previous literature has extensively explored PV system performance under various working conditions at the national [11,[29][30][31][32][33] or regional scale [34][35][36], the present research takes a more in-depth approach by considering local climate patterns at the metropolitan scale which have not been previously addressed. This site-specific approach may be relevant in densely populated metropolitan areas like Sydney, where overheating patterns are particularly various and pronounced.…”