The renewable energy-based power system stands as the most significant contributor to achieving a low-carbon campus. This study collects actual hourly energy consumption data from a dormitory in Beijing, China, to assess the viability of implementing a photovoltaic-battery system within the dormitory. The results reveal that the integration of the PVB design can lead to savings of up to 41.3% in the annualized cost of the power system, while also achieving a substantial self-sufficiency rate of 44.9%. Blindly increasing battery capacity reduces the economic benefits of the system; hence, it's crucial to make a reasonable selection of the energy storage scale. This study is expected to offer valuable insights for the campus carbon neutrality process.