The implementation of grid-connected, residential rooftop photovoltaic systems under different load scenarios in Malaysia

The current work discusses the implementation of grid-connected, residential rooftop photovoltaic (PV) systems under the scenario of low (300 kWh/month), medium (600 kWh/month), and high (2100 kWh/month) electric loads. The analysis shows that, under all load scenarios, using rooftop PV systems with increasing PV ratings increased renewable fraction (by at least 5% for 1 kW PV under high electric load to as much as 89% for 12 kW PV under low electric load) and reduced carbon emission (by at least 5% for 1 kW PV under high electric load to negative carbon emission for 12 kW PV under low electric load). Furthermore, the highest PV rating (12 kW PV) was preferred under low, medium, and high electric loads, with net present cost (NPC) 29%, 72%, and 29% lowered than the respective grid reference systems. Nevertheless, a long discounted payback period was required, especially under low electric load (above 20 yr). A few scenarios with regard to PV module price, PV sellback rate, tariff rate, and carbon tax were therefore analyzed, which led to NPC reductions of 20%, 40%, 40%, and 12%, respectively, for 6 kW PV under low electric load, in addition to shortened discounted payback periods. Although Malaysian data were used for analysis purposes, the current work has worldwide implications, where it serves as a techno-economic model that provides a sustainable development framework for understanding technically and economically the installation of rooftop PV systems for residential households and driving the implementation of rooftop PV installations especially across Southeast Asia.