Residential PV Hosting Capacity Under High EV Adoption: A Swedish Low-Voltage Grid Study

The increase in distributed generation and electricity demand at the residential level is becoming a key challenge for the stable operation of low-voltage grids. In particular, the interaction between solar PV penetration and EV charging demand has an impact on system reliability and infrastructure expansion needs, as it can both relieve and aggravate grid stress depending on when and where generation and demand coincide. This study investigates the performance of Swedish low-voltage grids at national scale, under future scenarios of passenger vehicle electrification, and alongside varying levels of rooftop solar PV deployment in single-family homes and apartment buildings.

Given that low-voltage grids are operated by numerous distribution system operators and subject to privacy constraints, we employ a synthetic grid model constructed from population density and geospatial data, validated against real-world measurements. EV charging demand is derived from large-scale datasets of real charging behavior across Sweden, while solar PV generation profiles are synthesized using GIS-based weather data and validated against measured production data from a representative region.

We perform year-long simulations with 15-minute resolution, using realistic household load profiles based on anonymized data from thousands of users. A linear power flow approximation is applied to quantify voltage violations and thermal overloads in cables and transformers.

Simulation results show that the amount of power system violations varies significantly depending on the degree of EV adoption and PV penetration, as well as the type of residential area (urban, suburban, or rural). We further quantify the transformer capacity expansion required across scenarios with varying levels of passenger car electrification and PV penetration. The results highlight the strong seasonal and geographical interplay between EV charging demand and solar PV generation in Sweden’s residential grids, characterized by high solar production in summer and prolonged periods of low generation in winter.