Commercial Battery
Storage Grants UK

The 2026 active stack includes Full Expensing (25% CT relief in Year 1, no application), 0% VAT on co-located solar + BESS, and Salix interest-free loans for public sector bodies (NHS, schools, councils, universities). IETF and PSDS both closed in 2024. Stacked, these reduce effective BESS net cost to 40–60% of gross capex for most UK commercial sites.

Commercial BESS costs £350–£550 per kWh of usable capacity installed in 2026. A 100 kWh system costs £35,000–£55,000 installed. Co-located with solar, 0% VAT saves 20% upfront; Full Expensing saves a further 25% via corporation tax in Year 1. Combined, a £50,000 BESS installation nets to around £30,000 effective cost for a profitable company.

Sizing depends on your half-hourly demand profile, peak demand periods, and solar array size. As a rough guide, target 1–2 hours of peak evening demand. For a 100 kWp solar system, 50–100 kWh of co-located storage is typical. We pull your AMR data and model the optimal charge/discharge strategy before recommending a system size.

Yes — NHS trusts, schools, councils and universities can access Salix BAU interest-free loans for standalone and co-located BESS projects. Projects range from £100k to £3m+. Repaid from energy savings over 5–12 years at zero interest. PSDS Phase 4 closed in November 2024 but Salix BAU loans remain open with no announced end date.

Standalone BESS payback on time-of-use arbitrage and peak demand avoidance is typically 6–12 years. Co-located with solar, BESS lifts self-consumption from 40–50% to 80–90%, accelerating the combined solar + BESS system payback to 3–6 years. Public sector Salix-funded projects effectively pay back from day one as loan repayments match modelled energy savings.