Analysing temporal factor in dynamic life cycle assessment of solar photovoltaic system

Abstract

Static life cycle assessment is a mature and widely used tool for quantifying the environmental performance of a solar photovoltaic system. The system’s lifetime is estimated to last for 25 years but there are cases that the whole system could ultimately be replaced or dysfunctional. This study proposed a dynamic life cycle model integrating time-varying factors to assess the cause affecting photovoltaic system performance over its expected lifetime and compare the scenario with a static life cycle analysis. Results show that the unpredictable weather in Malaysia causes a consistent drop in the module’s degradation rate, which significantly affects the system’s lifetime. A fixed assumption over a system’s lifespan could lead to a 20 % difference in the overall impact assessment. However, it does not significantly affect the static outcome, with only 0.05 years increment to the system’s energy payback time and 1.3 years longer on its return on investment. Conclusively, dynamic data changes the result by 5 % for environmental and 8 % for financial impact assessment. This proves that the unknown value hidden from the basic assumption in the static model can be defined by implementing the temporal elements into the dynamic model.