Load-match-driven design of solar PV systems at high latitudes in the Northern hemisphere and its impact on the grid

Abstract

Several challenges accompany the deployment of solar photovoltaic (PV) technology in residential construction, such as determining an optimum size and layout design for on-site utilisation that conforms to local roof-sloping practice. Common solar PV installation practice tends to prefer the Equator-facing orientation due to its maximised energy aggregate regardless of household load patterns. Solar PV applications in high-latitude regions encounter other challenges, such as significant seasonal variations in daylight hours and in the sun’s path. These challenges result in a PV mismatch: (a) in winter, minimal PV-generated energy and high energy demand (due to space and hot-water heating), and (b) in summer, PV over-generation and reduced energy demand. This study aims to provide a framework that identifies the best possible layout placement and size by applying the generalised reduced gradient nonlinear optimisation algorithm. In this regard, we monitor at one-minute intervals the energy performance of eleven single-family homes in Edmonton, Canada, some of which are net-zero energy homes and others of which are energy-efficient homes. Results show that in temperate climates at high latitudes in the Northern hemisphere, a south-west facing solar PV system installed at a tilt angle 10° above or below the local latitude can significantly improve the self-consumption compared to common installation practice.