Deployment of grid-connected photovoltaics (PV) in the UK has increased rapidly. By 2014 there were over 650,000 installations (over 5 GWp), spread over different market segments (on site of existing domestic and non-domestic electricity demand customers, or connected directly to the network, e.g. solar farms). This rapid deployment and diverse market segmentation raises questions about impacts upon the electricity network. Here the authors present a novel geographical information system framework which maps current PV deployment and electricity demand to sensitive spatial resolution and by market segment. This is used to understand how current PV deployment affects power flows between the high-voltage (HV) and low-voltage (LV) network. The analysis reveals that overall, current LV PV generation is significantly below summer daytime LV demand – with over half of the areas investigated showing electricity demand five times greater than peak PV generation. Interestingly a small number of areas exhibit peak PV generation greater than demand, where reverse power flow from LV to HV may occur. The framework is hence capable of identifying the areas where network impacts are likely to occur and will also be useful to consider how integration strategies, such as energy storage and demand response could facilitate further PV deployment.