Photovoltaic solar energy: Potentials and outlooks

This review focuses on modern energy attributes and to identify alternative energy source and technology that satisfy energy trilemma requirements. The results and findings of the study show that photovoltaic (PV) solar cells technologies have the potentials of satisfying the global energy quest if deployed more. This study x-rays the different PV cells technologies in terms of generation chronology, power conversion efficiencies (PCE), (EPBT), present status and outlook. This study harmonises many photovoltaic performance indexes from review as follow: PV module power conversion efficiencies (PCE) of solar cells: lab - mono-Si (26.7%), multi-Si (22.3%), CIGS (21.7%), for and CdTe (21.0%); commercial - mono-Si (17%), CdTe (16.0%); energy payback time (EPBT) in Europe, 1-1.5 years and 1.5-3.5 years for thin film and crystalline silicon PV systems, respectively, 3 months and 8 months for perovskite (PSC) and CdTe solar cells respectively. The price of PV has drastically declined from $76/W in 1997 to $0.3/W in 2015. By 2050 and 2100, PV solar technology is expected to provide 20% and over 60% of the world’s energy supply, respectively. This will account for 50% CO2 emissions reduction globally. The projections depend on further improvement on the performance indexes and lifetime, series resistance, and optical properties. CdTe technology performs better than other technologies at elevated temperature, hence, recommended for tropical regions.