Multi-objective optimization for sizing multi-source renewable energy systems in the community center of a residential apartment complex

Renewable energy systems (RESs) in urban areas must meet high energy demands with a limited space and satisfy the institutional requirements to reduce greenhouse gas (GHG) emissions. This study derives the RES design options that covers all building loads, meet the institutional requirements, and minimize the initial investment cost for a community center in an urban residential apartment complex. To achieve this, a multi-objective optimization method was employed. TRNSYS was used for the RES system analysis, and the main design variables of the RES were optimized using the developed tool. The Pareto solutions were obtained by differentiation of the initial design and they were derived through optimization. The optimal solutions required an initial investment cost that was 13.5–20.9% less than the initial designs and yielded an RES generation 5.2–24.4% higher than the initial designs. Therefore, they can sufficiently meet the institutional requirements.