Electricity consumption in net zero ready homes with ASHP and PV and its effect on power networks. A case study in the UK

• Comprehensive assessment of operational impact of low carbon dwellings on local power infrastructure. • 7 low-carbon homes with ASHP and PV constructed meeting UK’s Future Homes Standard are analysed. • Peak demand about 1/3 of the maximum power capacity of each dwelling. • Electricity consumption largely driven by occupancy behaviour. • Importance of diversity-based power network planning over theoretical capacity estimates. Low-carbon homes with enhanced insulation and airtightness, heat pumps and renewables are expected to be more energy-efficient. However, their real operational performance remains uncertain until inhabited. The performance gap between modelled and implemented energy systems is well documented. There is relatively little work showing the performance gap in practice for operational domestic heat pumps, particularly when combined with PV generation. This study examines the performance of 7 low-carbon homes constructed according the UK’s Future Homes Standard. It offers a comprehensive assessment of the operational impacts of low carbon dwellings on local power infrastructures, representing some of the earliest implementations of these new building regulations for future homes in the UK. A whole year of energy consumption data is analysed using a combination of regression techniques, graphical representations, and tabular data analysis to investigate operational energy performance, heat pump efficiency, peak power demand, and renewable energy utilization, providing novel insight to the implications of heat pumps on local power networks. The study reveals that measured diversified peak demand was just 14.6% of the total design capacity. Heating and cooking accounted for more than 80% of the peak power. While an average of 65% of solar energy generated was utilized within the homes, there remains scope to enhance PV energy integration by expanding the area of PV panels. These findings underscore that relying solely on theoretical or installed capacity could significantly overestimate actual network requirements and reinforces the importance of diversity-based planning and the role of occupancy patterns in shaping peak demand.