Examining The Techno-Economic Viability of Institutional Energy Generation Through Rooftop Solar Photovoltaic - A Case Study

Use of institutional rooftop solar photovoltaics (PV) is considered as a potential alternative toaddress energy deficit in low middle-income countries. This study aims to conduct techno-economicfeasibility assessment of rooftop solar PV taking a sample case of a school in Kathmandu valley.Comprehensive questionnaire survey and field measurement are done to determine load demandand energy usage habits of the institution. PVSyst is used to develop an optimized rooftop solar PVsystem with a total capacity of 72.6 kWp. Technical feasibility study is done through performanceratio and loss diagrams, and economic feasibility study is done through determination of paybackperiod. Performance ratio of 85% was achieved, and design losses are within acceptable range. Thehighest losses are seen in soiling and temperature derating which was below 4%. The designedsystem has an annual yield of 121.56 MWh, payback period of 6.7 years and return on investmentof 211.4% after the payback period. For validation, the simulated results are compared with datalogged in a comparable institution with a net metering system. The simulation for this institutionwas carried out using an identical regime. The payback period of 11.5 years was empiricallycalculated through the logged generation/usage data whereas the simulation result showed apayback period of 11.8 years, which is in acceptable range. This study shows that institutionalrooftop solar PV is both technically and economically viable in Nepal.