A Comprehensive Assessment of a Rooftop Grid-Connected Photovoltaic System: A Case Study for Central Vietnam

Xuan Cuong Ngo, Thi Hong Nguyen, Nhu Y Do


This paper presented an actual comprehensive assessment of a 1.32 kWp rooftop grid-connected photovoltaic system for residential buildings in Central Vietnam under the tropical monsoon climate. Operational parameters of the grid-connected photovoltaic system were monitored from August 2020 to July 2021. It consists of four photovoltaic modules, a microinverter, and a two-way energy meter. The analysis results of energy performance provided a performance ratio of 78.11%, a capacity utilization factor of 15.07%, and an annual overall system efficiency of 12.89%. In addition, the financial and environmental analysis of the system also indicated that the levelized cost of electricity was pretty low (i.e., 0.063 USD/kWh), the discounted payback period was 5 years, and 1.5 tons CO2 was reduced per year. The results of the analysis were compared and evaluated with other grid-connected photovoltaic systems in the same Southeast Asia region, and they revealed that the integration of the grid-connected photovoltaic system into the distribution grid in Central Vietnam is superior. The obtained data can be used as a guide for applying grid-connected photovoltaic systems in other locations with similar climates, as well as to assist the government in developing a more appropriate rate of feed-in-tariff for real-time grid-connected photovoltaic systems.


FiT; Grid-connected; Photovoltaic; Rooftop; Vietnam

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