Life-cycle-assessment based design of a standalone photovoltaic system: a case study using a theoretical and numerical approach

Abstract

Greenhouse gas emission from conventional energy system and growing demand for energy result in the use of renewable energies such as solar energy. This study aims at designing life-cycle assessment (LCA) of a standalone photovoltaic (PV) system to meet the electricity demand of building in the diverse climate of India using a theoretical and numerical approach. The electricity demand is estimated on the daily basis considering all the power consumption equipments and their operational hours. Then, the suitable components of the PV system are selected based on their specification and available rooftop space. In the LCA analysis, environmental as well as financial analysis of the PV system is performed. For the environmental assessment, carbon credits are evaluated, whereas internal rate of return (IRR), net present value (NPV), levelized cost of electricity (LCOE) and the payback period of the PV system are estimated for the financial evaluation with consideration of inflation rate and effective discount rate. The PV system is found to be economically feasible because the NPV of this project is positive. The entire solar PV system is also simulated using PVSyst software, and results such as economic feasibility, performance ratio, input/output diagram, incident energy and array output distribution are compared with the theoretical calculation. Moreover, losses at various stages, as well as the reliability of the PV system, are analyzed. The peak rating of the building came out to be 232.71 kWp. The energy payback time and LCOE for the PV system are 7.43 years and $0.076/kWh, respectively, with a life-cycle conversion efficiency of 0.069.