London retail distribution solar: Tesco Welham Green NDC (Hertfordshire), Sainsbury's Charlton DC (SE7), M&S Castle Donington (adjacent), Waitrose Bracknell, John Lewis Bracknell — plus Park Royal and Heathrow retail NDC operators. London grid tariffs: 23-28p/kWh (highest UK). UKPN G99: 4-8 months. Self-consumption automated grocery NDC: 88-94%. Payback 4-5 years.
Local context — London
London retail DC solar: UK's highest grid tariffs (23-28p/kWh) + UKPN G99 + major retailer Scope 3 (Tesco Net Zero, M&S Plan A, Waitrose JLP) = fastest payback of any UK logistics hub. 88-94% self-consumption grocery. 4-5 year payback.
Modelled scenario — London
A 2 MW solar PV install at a London M25 grocery retailer NDC. UKPN G99: 6 months. Grid tariff: 26p/kWh. Self-consumption 91%. Annual saving: £476,000. Simple payback: 4.1 years. Tesco Net Zero audit pack: delivered at handover.
Common questions — retail distribution in London
Why does London retail DC solar have the best payback despite high costs?
London grid tariffs (23-28p/kWh) are the primary driver — each kWh of self-consumed solar is worth 25-35% more than in the Midlands or North. On a 2 MW London install: annual saving is £60,000-£120,000 higher than the identical system at a Midlands equivalent. The tariff premium more than offsets any higher installation costs in London.