Performance of Bifacial Photovoltaic Modules on a Dual-Axis Tracker in a High-Latitude, High-Albedo Environment

Abstract

Bifacial photovoltaic dual-axis tracker systems have the potential to out-perform other module/mounting configurations at high latitudes, where the reflectivity of snow in winter boosts bifacial performance and the low solar angle-of-incidence favors dual-axis tracking. Two years of empirical data from dual-axis experimental systems in Vermont support this assertion, demonstrating that bifacial modules on a dual-axis tracker produced 14 percent more electricity in a year than their monofacial counterparts and as much as 40 percent during the peak winter months. These bifacial gains are in addition to the estimated 35-40 percent energy gains of a dual-axis tracker relative to a fixed-tilt system. Such findings suggest that bifacial two-axis tracker systems could be economically attractive in northern latitudes, with high-efficiency modules compensating for the trackers’ installation and maintenance costs, and future design improvements enabling further performance gains.