Perovskite solar cell (PSC) technology is the flag bearer for the future of photovoltaics allowing unlimited possibilities for its application. This technology is currently limited by issues related to its scale-up, stability and the composition of the materials used in its preparation. Using small sized solar cells with higher efficiency under solar concentration is gaining traction as a methodology for scaling up this technology and broadening its applications. However, this has only been reported in devices with size <1 mm² neglecting the series resistance of the device. Here, we report the performance of a 9 mm² PSC at varying solar concentration levels and correlate it with the series resistance of the solar cell. The n–i–p structured device using a triple cation perovskite absorber with a mesoporous titanium oxide/SnO₂ layer as the electron transporting layer and Spiro-OMeTAD as the hole transporting material achieved a peak efficiency of 21.6% under 1.78 Suns as compared to the 21% obtained under 1 Sun (1000W m⁻²) and AM1.5G. We further boosted the power output up to 15.88 mW under 10.7 Suns compared to the 1.88 mW obtained under 1 Sun; however this results in an actual efficiency drop of the PSC owing to the device series resistance. Further, we investigated the impact of the increasing solar cell temperature at higher concentration levels and identified the influence of series resistance on the performance of the PSC. Our work identifies the potential of concentrating photovoltaics and highlights the challenges and makes recommendations for future development.

The continuous growth in the energy demand across the globe due to the booming population, in addition to the harmful effects of the fossil fuels on the environment, has made it essential to harness renewable energy via different technologies and convert it to electricity. The potential of solar energy still remains untapped although it has several advantages particularly that it is a clean source to generate both electricity and heat. Concentrating sunlight is an effective way to generate higher throughput per unit area of the absorber material used. The heat extraction mechanisms and the fluids used in solar thermal systems are key towards unlocking higher efficiencies of solar thermal systems. Nanofluids can play a crucial role in the development of these technologies. This review is aimed at presenting the recent studies dealing with cooling the photovoltaic thermal (PVT), concentrated photovoltaic thermal (CPVT), and other solar systems using nanofluids. In addition, the article considers the definition of nanofluids, nanoparticle types, nanofluid preparation methods, and thermophysical properties of the most common nanoparticles and base fluids. Moreover, the major factors which affect the nanofluid’s thermal conductivity according to the literature will be reviewed.