Best tilt of PV system in Canada: Effect of the sky radiation model and climate conditions

Abstract

This paper focuses on the best tilt angle of photovoltaic applications, to be related to the latitude and a latitude correction factor here presented. The analysis includes a series of 19 cities across Canada: latitude and local weather conditions are considered to define a correction angle correlation. This correction is expressed as a function of latitude, average annual weather conditions, and yearly climate variability, demonstrating strong alignment with “exact” outputs (correlation coefficient equal to 0.98 for different sky models). To ensure broad geographic coverage, Typical Meteorological Year hourly data were obtained from the Canadian Weather Year for Energy Calculation portal. The validity of the correction was assessed against various approaches and web tools results. Results were then compared with those from European cities at similar latitudes. Findings indicate that determining the optimum tilt angle requires accounting for latitude and site-specific climatic conditions, including snow cover: snowy regions benefit from higher tilts, emphasizing the relevance of considering accurate albedo in photovoltaic system design. Results suggest that this precise tilt calculation can yield annual insolation gains of up to 3.5 % with respect to rule-of-thumb angles (i.e. tilt equal to latitude), even at lower latitudes, with variations in best tilts until 13°.