Potential lighting and thermal demand reduction in office buildings using blind control considering surrounding buildings

Abstract

Automated blind control has been found to be more effective in controlling solar penetration than manual blind operation. Existing automated blind control methods mainly focus on improving indoor conditions, but considering the outside obstructions may offer a potential method to admit diffused solar radiation, reducing lighting, cooling, and heating demands. Accordingly, in this study, blind control considering surrounding buildings (BCCSB) was applied to determine potential demand reductions considering 20 736 cases of different surrounding building heights, orientations, locations, and climate change projections using EnergyPlus. The results demonstrate that BCCSB can reduce lighting demand by up to 30% when the building obstruction angle is greater 30°; however, this reduction decreased as the angle factor between the fenestration surface and sky decreased due to the accompanying reduction in admitted diffused solar radiation. The reduction in lighting demand also reduced the cooling demand as fewer active lighting fixtures were required. The use of BCCSB did not significantly reduce heating demand. The BCCSB can thus facilitate the reduction of lighting and cooling demand in highly glazed buildings, especially in warm climates. This evaluation of the positive effects of BCCSB can help to develop related design guidelines, standards, and practices for automated blind control strategies.