Simulation study on energy conservation performance for integrated external louver facades

The authors previously proposed integrated-facade-systems comprising different types of external louvers integrated with buckling restraint braces. The systems can be applied to both new and existing buildings, paying attention to the building’s appearance, upgraded structural performance and indoor environment. The authors have studied indoor daylight conditions with louver facades and a research paper was published in this journal (Misawa, Hikone, Nakamura, Iwamoto, Iwata, 2014). This research study reports on the energy conservation performance of louver facades and proposes an External Shading Coefficient (ESC) for external louver systems. Situations with five external louver facades and no louvers, facing three facade orientations (East, South and West) are examined. The year-round ESC is simulated every hour using Radiance software for transient solar radiation calculations. Furthermore, by using the proposed ESC, case studies for typical Japanese offices are carried out to verify reduction effects on the annual thermal load and electrical energy consumption of an air source heat pump for each louver set-up. Simulation results are calculated in hourly increments using TRNSYS software; the results show that both thermal loads and electrical energy consumption are reduced regardless of louver types and facade orientations when integrated external louver facades are installed.