Solar energy for residential electric vehicle charging in Northern Norway – a feasibility study

Abstract

This paper presents a study of the potential for using photovoltaic (PV) solar energy systems for residential charging of electric vehicles (EVs) in Northern Norway. The objective is to investigate the load match between PV yield and uncontrolled EV charging, in terms of self-consumption and self-sufficiency. The load profile for EV charging is retrieved from a study by the Norwegian Water Resources and Energy Directorate (NVE), based on measurements and a survey sent to EV owners. An adjusted example EV profile that better represents a single household is also proposed. Other household loads are taken into account using measured data from ten single-family buildings in Tromsø, retrieved from local power company Troms Kraft. The PV yield is simulated for roof-mounted and façade-mounted 4.2 kWp system with different orientations, using PVsyst. The results show that the load match between PV yield and uncontrolled EV charging is poor, as PV power has a peak at noon and the EV charging is highest during afternoon and night-time. A design option for increased load-match (but lower total yield) is mount the PV system facing west, since the PV power peak is shifted towards the afternoon. Solutions for increasing the load match, provide autonomy and reduce negative impacts on the grid are discussed, for example the use of residential battery storage and controlled EV charging. Based on the results, the authors propose that more focus is given to workplace charging combined with solar energy, since this would increase the load match significantly.