In-Roof Solar and Battery Storage on a Grade II Listed Cardiff Church

The Gate Arts Centre is a community-focused arts and events venue in Cardiff, housed in a beautifully restored Grade II Listed former Victorian church. As a registered charity, it runs a year-round programme spanning theatre and comedy, jazz nights, poetry readings, conferences and training, alongside community uses like baby classes, a food co-op and church services - a small organisation with substantial reach across the local community.

The Gate reopened in 2004 following a major restoration, and approached Inspire Green looking to install solar power to support the wide range of activities now housed within the building. After the solar PV install, The Gate came back to discuss adding battery storage and infrared heating to minimise their dependency on the grid. What started as a solar install grew into a full decarbonisation project.

Phase 1 - In-roof Solar PV (22.10 kWp). The original planning permission proposed an on-roof system, but the added weight on the listed structure was a concern. We liaised with Cardiff Conservation officials, the architects and the engineers to revise this to a much lighter in-roof system, flush with the slate. Fifty-two Trina 425 W modules were installed, paired with a SolarEdge 25 kW inverter and per-panel optimisation. The array takes a load off the building rather than adding to it, and presents a far cleaner aesthetic than a conventional bolt-on array would have done on a listed church.

Phase 2 - Battery Storage (43.6 kWh) & Herschel Infrared Heating. With solar alone, 7.35 MWh a year was being exported back to the grid at low rates. We added a SolarEdge Home Battery 48V system, AC-coupled to the existing inverter and running in Time-of-Use Optimisation Mode. Self-consumption rose from 34% to 45% and annual grid export dropped by 78%. Gas heating was replaced with Herschel infrared panels - zonal, instant-response, with no flue or wet system, and increasingly powered by the venue's own solar and battery.