Economic Feasibility and Greenhouse Gas Reduction Analysis of Installing a Solar Rooftops on Dormitory Buildings at Thammasat University, Rangsit Campus

Abstract

Solar energy is an environmentally friendly energy that supports Thailand's goal of achieving carbon neutrality. This study analyzed the economic feasibility of installing rooftop solar photovoltaic (PV) systems on dormitory buildings at Thammasat University Rangsit Center to reduce electricity consumption from the grid. The results show that the optimal installed capacity is 1.4 MWp, which can generate approximately 1,881,337 kWh/year, equivalent to a reduction in greenhouse gas emissions of 914 tCO₂e/year. The economic feasibility analysis shows that the project is economically viable. The levelized cost of electricity (LCOE) is between 2.34 and 2.68 baht/kWh, and the internal rate of return (IRR) is between 15.35% and 18.45%. The payback period is approximately 5-6 years. A sensitivity analysis was conducted considering the following factors: (1) self-consumption ratio, (2) solar cell degradation rate, and (3) operating and maintenance cost. The results show that the self-consumption ratio is the most critical factor affecting the project's viability. The project is viable only if the self-consumption ratio is higher than 60%. The other two factors do not significantly affect the project's viability.