Charities run on tight budgets. Every pound spent on electricity is a pound not spent on their mission. We designed this system around that constraint: generate as much as possible during the day, store the surplus, and keep evening operations running on battery rather than imported grid power.
The brief
The premises run a mixed load across a three-phase supply — lighting, office kit, and higher-draw equipment during daytime activities. A single-phase system would only offset one phase of the load, leaving the other two importing at full rate regardless of how much sun was on the roof. We needed a solution that balanced generation and discharge across all three phases.
What we installed
- 10 kWp solar array sized to the available roof space and the site’s annual consumption profile
- 20 kW three-phase hybrid inverter — handles solar, battery, and grid interaction in a single unit, balanced across all three phases
- 20 kWh lithium battery storage — enough to carry evening loads without pulling from the grid
- Real-time monitoring so the trustees can see generation, self-consumption, and savings at a glance
Why three-phase matters here
On a three-phase supply, every watt of solar and every watt of stored energy only cuts the bill if it lands on the phase that’s drawing at that moment. A proper three-phase inverter balances output across all three phases automatically — so the whole site benefits, not just a third of it.
Outcome
Commissioned April 2026. Over a full year, the system is sized to cover the majority of the charity’s daytime consumption directly from solar, with the battery carrying base load into the evening. The result: a meaningful reduction in grid import, and a predictable energy cost for a charity that needs every bit of budget certainty it can get.