Rising electricity costs and increasing interest in renewable energy have encouraged the adoption of rooftop solar photovoltaic (PV) systems in urban commercial buildings. Nevertheless, investment decisions remain challenging due to uncertainties in system performance and financial returns under local operating conditions. This study presents a techno-economic feasibility assessment of an on-grid rooftop solar PV system using a case study of an office building in Bangkok, Thailand. The technical analysis considers solar irradiance characteristics, local climatic conditions, and system performance indicators, including temperature-related losses and performance ratio (PR). The economic evaluation applies standard financial metrics, including net present value (NPV), internal rate of return (IRR), payback period, and electricity cost savings to assess investment viability under Thailand’s electricity tariff structure. By integrating technical performance with financial evaluation, the proposed approach emphasizes decision-oriented analysis rather than energy yield alone. The study is expected to demonstrate the practicality of rooftop PV systems for urban office buildings and to identify key factors influencing both performance and economic outcomes. The proposed assessment framework can support decision-making for stakeholders considering rooftop solar investments and may be extended to similar commercial building applications in emerging urban contexts.

Keywords

Rooftop solar PV; Techno-economic feasibility; Urban office buildings; On-grid photovoltaic system; Energy cost savings.