Solar energy is harnessed from the sun by photovoltaic cells that convert sunlight into electricity. The process of converting the sun’s rays into electricity is called the photoelectric effect. It presents as a sustainable source of energy that can reduce carbon emissions and tackle climate change. But with growing extreme weather conditions what could be the effect on solar panels? Here is what you need to know about how weather conditions affect the panel’s operation and efficiency. Solar panels perform well in sunny weather because with no clouds in the sky the transmitted sunlight directly hits the panels. Clouds reduce the amount of sunlight that can hit the panels, so on a cloudy day they don’t produce as much electricity as they do on a sunny day. A study was done by the University of Brighton in the UK to investigate how weather conditions affect the efficiency and operation of solar panels in the southeast of the UK. The effect of weather conditions on the performance of PV panels was demonstrated through analyzing the system outputs of two existing solar PV installations. Results revealed that high humidity and rain particularly have the most significant effects on the efficiency of the two PV installations [1]. A similar study was done by Shahid Beheshti University in Iran, for 70 days. Results revealed that after 70 days without rain dust was accumulated on the surface of the panels, which caused a 21.47 (%) reduction in the power [2]. Solar panels can perform well in colder and sunny weather. In places like southern Florida, where extreme winds occur every year because of hurricane season shouldn’t be a concern as solar panels are manufactured and engineered to withstand winds up to 170 Mph [3]. As for very hot climates, the performance can drop this happens because the solar panels give maximum power output at 25 ֯ C for every increase in module temperature by 1 ֯ C the efficiency decreases. This decrease in efficiency varies between -0.3% / ֯ C to -0.5% / ֯ C. This is known as the temperature coefficient. This can be found in the manufacturer's datasheet. As for winters, the ambient temperature can help in improving the performance of the solar panels as long as the panels aren’t covered in snow. In recent years innovations have been made to develop solar panels to minimize the effect of weather conditions like for example self-cleaning and hydrophobic coatings are common methods available when installing new solar panels. Different weather conditions have an impact on the type of PV cell technologies. The PV market is dominated by monocrystalline and multicrystalline silicon wafers, followed by thin-film technology. Studies have shown that different PV cell technologies have their own merits and demerits in different weather conditions. This article will focus mainly on monocrystalline and multicrystalline silicon panels. Monocrystalline solar panels are relatively a premium product compared to their multicrystalline counterpart. Monocrystalline panels perform better because they are produced by using silicon wafers which have a single crystal orientation whereas multicrystalline panels are made using chunks of silicon with different crystal orientations. This is the main reason why monocrystalline silicon panels have higher efficiency compared to multicrystalline silicon panels and they are also more expensive to produce. Another advantage is monocrystalline panels have high heat tolerance. A study performed by VIT University from India analyzed the performance of monocrystalline and multicrystalline cell technologies under different weather conditions. On a sunny day, it was observed that monocrystalline panels produced more power compared to their multicrystalline counterparts. Similar results were observed in cloudy weather conditions. It was also shown that relative humidity has an impact on the performance of the panels due to the reflective factors which affect the irradiance levels [4]. In all the cases monocrystalline panels performed better than multicrystalline panels. This comparative analysis gives a clear understanding of the performance of different PV modules under varying weather conditions and also gives a good insight into the selection of the right technology for a particular environment.
