Optimal decision-making of renewable energy systems in buildings in the early design stage

Renewable energy systems (RES) in buildings should be designed carefully, not only because of the need for an optimal design, but also to comply with related laws. Therefore, the design of RES in the buildings requires close collaboration between architects and engineers from the beginning of the design process. To support such collaboration, this study proposes a simplified design method for RES in buildings during the early design stage. By using the proposed design method, design alternatives that meet the required energy standards as suggested by law are first generated. Further designs are made to evaluate the performance and cost of the design alternatives and to find the optimal types of RES for the building. The study also uses a case study to verify the applicability of the design method to the early design stage. Although the performance and cost of the different design alternatives are similar, the implementation of each type of RES in each design alternative is different. Nonetheless, by analyzing performance patterns and the cost ratio of each type of RES in each design alternative, the study allows the most suitable type of RES to be chosen for the building.