Journal of Korean Institute of Architectural Sustainable Environment and Building Systems ISSN:1976-6483(Print) 2586-0666(Online) 한국건축친환경설비학회논문집

Photovoltaics (PV) is one of the new and renewable energy types, which has a high design degree of freedom of device capacity due to the installation characteristics of module-level without making noise, and its application cases in buildings have increased. Moreover, a measure to increase power generation using sun location tracking and reflective plates has also been studied highly actively to overcome the limitation of efficiency of power generation modules and outdoor solar radiation. In this context, this study deals with the change in power generation in a bidirectional reflectance PV (BRPV) array, which uses reflected light on the surface by installing two PV modules at 90° position to each other. The single horizontal and vertical PV arrays and BRPV were installed at the rooftop of a building in the metropolitan city and each power generation was measured for one year from May in 2019. The increasing trend of power generation was found in the horizontal panel when the solar meridian altitude was increasing whereas the vertical panel power generation increased when the solar altitude angle was decreasing. The cumulative annual power generation showed that the horizontal array in the BRPV was the largest followed by a single horizontal array, BRPV vertical array, and single vertical array. In addition, the increase in power generation due to the reflected light effect of the BRPV array was verified as the solar altitude angle was lower as shown in a monthly increase of –0.3–20.1% and an annual average increase of 8.6% in the horizontal panel. The power generation from the vertical panel of the BRPV increased by 6.3–82.9% monthly and its power generation increased by 32.8% compared to that of the independent vertical panel annually.