The commercial battery business case
Most UK commercial electricity bills include kVA capacity charges (Triad charges on half-hourly contracts) of £40-£120 per kVA per year. A 50kW battery managing peak demand reduces capacity charges by £2,000-£6,000 annually. Add off-peak/peak arbitrage on a half-hourly tariff (charge at 6p/kWh overnight, discharge against 25p+ peak rates) and solar self-consumption uplift, and a typical 100kWh system pays back in 6-9 years.
When commercial battery makes sense
Strongest cases: businesses on a half-hourly contract with kVA charges, businesses with large solar arrays (>100kW), businesses with shift patterns that mean strong evening or overnight load (cold stores, datacentres, manufacturing 2/3-shift). Weakest cases: small SMEs on standard non-HH tariffs without much electricity exposure.