According to André Nobre, project manager of Solar Energy Systems at Solar Energy Research Institute of Singapore (SERIS), one of the most important points to consider when developing a rooftop PV system for tropical regions is the distance between the module and the rooftop.
As part of a study launched by SERIS, Nobre collected and analyzed data concerning 11 wafer-based crystalline technology PV systems in Singapore. The systems utilize a mixture of crystalline and thin-film modules but all were rooftop systems as Singapore’s lack of space made it difficult for ground-mounted PV systems to be installed.
Presenting the findings of this study at the Large PV Power Plants and Distributed PV System Aspects and Grid Integration session at EU PVSEC this week, Nobre revealed that the larger the distance between the modules and rooftop, the higher the performance of the PV system. This, coupled with well ventilated sites, will help to reduce negative temperature impact. Nobre recognized that this would be more costly to implement but stressed that it would improve the performance of the PV system.
Nobre also suggested that PV systems for Singapore and tropical regions should be tilited by a minimum of 10 degrees in order to minimize dirt accumulation. This is despite the latitude which appears to be more suited for flat installations.
Other areas to consider when developing PV projects for hotter climates, as highlighted by Nobre, include ensuring proper sizing and close attention to inverters, and options to minimize shading.