This paper evaluates the effectiveness of CO2e emission reductions achieved by the Hoà Hội solar power project, a major renewable energy project in Vietnam. Operating since June 2019, the plant, with a capacity of 257 MWp, demonstrates substantial potential in reducing greenhouse gas emissions by substituting fossil fuels with solar energy. The study assesses electricity production from June 2019 to July 2024, revealing significant annual output variations influenced by seasonal sunlight and irradiance. It also analyzes the impact of CO2e reduction, calculating a total reduction of approximately 1.34 million tons of CO2e, equivalent to planting between 30 and 60 million trees. Additionally, the plant's adoption of International Renewable Energy Certificates (I-REC) is estimated to potentially generate approximately 1 million USD in revenue, highlighting the economic viability of renewable energy projects. The findings affirm the plant's role in mitigating climate change and its contribution to sustainable development. The results underscore the dual benefits of renewable energy projects in both environmental impact and economic returns, advocating for continued investment and policy support in the sector.