A 1 MW warehouse solar system is mainstream commercial scale for UK distribution centres, large fulfilment, and cold chain. With 1,850 panels covering 6,000-9,000 sqm of roof, fits 200,000-300,000 sqft buildings. Capex sits at the AIA cap so half is fully expensed year 1 (£250k tax shield), residual £150-200k falls into 50% FYA. PPA financing well-established at this scale.
Typical 1 MW system specification
Capacity: 1 MW. Panels: 1,850 modules at 540W. Roof area: 6,000-9,000 sqm usable. Inverters: 8-12 string inverters or 1-2 central inverters. Annual generation: 920,000 kWh. Capex: £700-800k installed. AIA + FYA tax shield: £225k + £75k = £300k year 1. Payback: 4-5.5 years.
When 1 MW is the right size
Distribution centres 200,000-300,000 sqft. Large fulfilment centres (Amazon-customer scale). Mid-large cold chain facilities. Manufacturing with continuous process load + cold storage. Retailer RDCs (mid-size grocery and high-street). Most institutional landlord (Prologis, Tritax) building stock.
Economics worked example
1 MW install on a 280,000 sqft DC: capex £750k. Year-1 tax shield £225k AIA + £63k FYA = £288k. Net cash cost £462k. Annual generation 920,000 kWh. At 80% self-consumption: £162k/yr saving + £20k SEG = £182k. Simple payback 4.1 years. After-tax cash 2.5 years. 25-year IRR 25%.
Common questions about 1 mw system
Why is 1 MW so popular for UK warehouses?
It's mainstream commercial scale. Most institutional landlord building stock (Prologis, Tritax, GLP, Blackstone, Segro DCs) sits at 200,000-300,000 sqft — perfect 1 MW fit. PPA financing well-established at 1 MW+. AIA + FYA stacking delivers £288k year-1 tax shield. Strong payback economics.