Development and verification of a slat control method for a bi-directional PV blind

Abstract

Photovoltaic (PV) blinds are a set of venetian blinds with a new concept and various functions. In addition to the existing function of shielding direct sunlight, energy is generated using a PV module. Ordinary blind control is determined by considering the profile angle of the Sun, and the uni-directional control method creates a shaded area between the blind slats. This design reduces the utility of the PV blinds by disrupting the inflow of skylight and energy generation. Therefore, a different method than the conventional blind control method must be used. The PV blinds must be controlled by limiting the inflow depth of direct sunlight and allowing the maximal inflow of indoor skylight to optimize PV power generation. In particular, the bi-directional PV blinds used in this study conserve lighting energy and generate solar energy through bi-directional control. An appropriate slat control method was proposed, and an actual office space was created. Measurement data from uni-directional and bi-directional control rooms with the same dimensions were comparatively analysed. The results indicated that the average illuminance of the uni-directional control room was only 21.86–38.86% of that of the bi-directional control room, and the average power generation of the uni-directional control room was 85.05–110.88% of the bi-directional control room.