RHS Rosemoor

The brief

Rosemoor is one of the four flagship gardens of the Royal Horticultural Society - 65 acres of formal gardens, woodland and visitor facilities on the edge of Great Torrington. As part of the RHS's wider sustainability commitment, they needed renewable generation at scale, across the three buildings that draw the most electricity: the visitor centre and café, the events space, and the exhibition room.

We won the work through competitive tender. The brief was simple to understand but harder to deliver: a large-scale system, three different roof types, three different mounting approaches, and a site that had to stay open to the public throughout.

What we installed

• 290 × Aiko 470W all-black panels

• 3 × SolarEdge three-phase 33.3kW inverters with dual-panel optimisers across the array- 99.9 kWp total

• Three mounting systems on one project: Renusol standing-seam clamps for metal roofs (no roof penetration), Esdec ballasted system for flat-roof sections, and GSE in-roof system where panels sit flush with the slates

• Live monitoring across all three buildings through SolarEdge's platform

The GSE in-roof work was where the project earned its keep. Flush-fit slate roofing on a visitor-facing building leaves no room for sloppy detailing - the panels become the roof.

The result

• ~118,000 kWh of clean electricity generated per year across the three buildings (based on full-year simulation)

• ~24 tonnes of CO₂ avoided every year versus grid average

• A material contribution to the RHS's wider net-zero commitment

• Installed September–November 2024, with the gardens open to visitors throughout