Impact of residential photovoltaic systems on net load intermittency

Abstract

The addition of solar photovoltaic (PV) generation can negatively impact electricity grid stability due to both the intermittency of generation and temporal misalignment of generation and load. This has led to some jurisdictions enforcing ramp rate limitations on PV generation, and a growing interest in PV intermittency mitigation using energy storage. We evaluate residential PV and load intermittency using measured data from a municipality. Power ramp rates caused by residential loads and PV generation were compared. The datasets were also used to generate synthetic net load profiles to evaluate how adding PV to a home impacts ramp rates as seen by the electricity grid. Additionally, an energy storage model was used to estimate the capacity of battery required to mitigate ramp rates. Residential load profiles were found to have more extreme normalized ramp rate distributions than residential PV systems. The addition of PV systems to homes resulted in a 0.012% increase in ramp rates exceeding 10% of the maximum annual load per 5 minutes when aggregated, meaning PV variability is negligible compared to residential load variability. Consequently, mitigating PV ramp rates using energy storage had almost no impact on residential net load variability.