An assessment of the potential for solar PV electricity generation from rooftops in Northern Ireland

This research was commissioned by the Departtment for Economy for Northern Ireland to assess the potential of Rooftop Solar PV generation in Northern Ireland and associated battery storage.

Key Conclusions

•Solar PV is a mature technology that can make a significant contribution to electricity generation in Northern Ireland.

•A typical 4kWp residential PV will meet on average 28% of household electricity demand, with this increasing as the solar PV system size (kWp) increases.

•The current Micro Generation Solar PV G98/NI registration process limit of 3.68 kWp (4kWp) for single phase installations has become the de facto residential PV system size.

•PV installation rates showed a rapid decline after the ending of the ROCs scheme in 2017, while there was a slight recovery in installation rates in 2022 and 2023. There is unlikely to be a substantial uptake of PV in the domestic sector without the introduction of a financial incentive scheme (in addition to the current export tariff payments) for households to meet some of the capital costs of installing the technology.

•The potential utility of PV can be significantly enhanced by the addition solar plus technologies such as PV water heating and battery storage. These technologies enable households to potentially consume 70% plus of their PV electricity generation.

•In magnitude, rooftop PV generation could on an annual basis exceed Northern Ireland’s electricity demand, however significant mismatches occur between PV generation and demand especially during the months November through to January