A robust DCF is the standard for warehouse solar board approval. Here's how to build one — and how to validate any model an installer sends you.
DCF model structure
(1) PVSyst yield: year 1 kWh, 0.35-0.45%/yr degradation, P50/P90. (2) Self-consumption profile: HH meter data × generation profile. (3) Revenue: self-consumed saving + SEG export. (4) Capex: EPC + DNO + structural + design. (5) Tax: AIA year 1 (up to £1m, £250k shield at 25% CT), 50% FYA above £1m. (6) Opex: O&M £5-8k/yr per 500 kW, monitoring, insurance. (7) Terminal value: year 25 residual.
PVSyst validation
Accept: Meteonorm 8.1 or SolarGIS GHI source. 3D shade scene. Module degradation per manufacturer spec. PR 79-83%. Our models: typically within 2% of measured first-year actual generation.
Self-consumption from HH data
Request HH export from energy supplier. Overlay PVSyst hourly output. Cold store: 87-94%. Logistics: 72-82%. Cross-dock/intermittent: 65-77%. Our models: within 5% of measured outturn.
Grid tariff sensitivity
Base: current tariff, no real growth. Sensitivity: +2%/yr real (payback 0.5-0.8yr faster); flat (standard); -1%/yr real (payback 0.3-0.5yr slower). Solar delivers positive NPV in all three. Always show sensitivity table in board submission.
Correct tax treatment
AIA: first £1m = £250k shield. FYA 50%: above £1m = £50k shield per £200k. Freeport ECA: 100% additional allowance on qualifying assets. After-tax cash payback typically 1-2 years faster than simple payback.
See more
DCF guide: /guides/warehouse-solar-dcf-model/. Finance guide: /guides/warehouse-solar-finance-options/. Contact: /contact/.