IETF Phase 3: eligibility criteria you must meet
The Industrial Energy Transformation Fund (IETF) Phase 3 is administered by DESNZ. To be eligible for IETF solar PV grants, your business must meet all of these criteria. (1) Manufacturing or industrial process: SIC codes 05-39. Pure logistics/warehousing without manufacturing process is NOT eligible — the facility must have qualifying industrial process on site. (2) Energy consumption: above 1 GWh total site energy per year (electricity + gas combined). Annual energy spend above approximately £180,000 typically indicates 1 GWh+ consumption. (3) Project type: capital investment in energy efficiency or low-carbon technology — solar PV qualifies. (4) Minimum project size: £100,000 capital cost. (5) UK establishment: the applicant must be a UK-registered business.
Step 1: Check eligibility and estimate grant percentage
Grant percentage is determined by site energy intensity: 30% grant for sites consuming 1-5 GWh/yr; 40% for 5-20 GWh/yr; 50% for above 20 GWh/yr. To estimate your consumption: review your last 12 months of electricity and gas bills. Most manufacturers above 200 employees will be above 5 GWh/yr total site energy. We provide free eligibility assessments and grant percentage estimates as part of our pre-application service.
Step 2: Expression of Interest (EoI)
The IETF application begins with an online Expression of Interest via the DESNZ grants portal. The EoI requires: company registration details and SIC code; site address and NAV (Net Annual Value) rateable value; estimated annual energy consumption; brief description of proposed project; estimated capital cost. EoI processing time: 3-4 weeks. DESNZ confirms eligibility and invites to full application. The EoI does not commit you to a specific contractor or system specification.
Step 3: Energy audit to ISO 50002 standard
A full IETF application requires an energy audit report from a qualified energy auditor. Requirements: auditor qualified to ISO 50001 Lead Auditor standard or equivalent; audit scope covers the whole site; audit identifies current energy use baseline (kWh/yr by fuel and end-use); audit establishes the energy performance baseline against which the solar saving is measured. Audit cost: £3,000-£8,000 depending on site size and complexity. Timing: allow 4-6 weeks for audit completion after site visit.
Step 4: Full application
The full IETF application includes: energy audit report; project technical specification (system size, inverter spec, generation estimate); contractor quotes (minimum two quotes required); project business case with NPV, IRR, and payback calculation; state aid declaration; supporting accounts (last 2 years audited accounts). Full application processing: 8-12 weeks. DESNZ may request additional information — respond within 10 working days. Grant offer letter issued subject to project conditions.
Step 5: Project delivery and grant claim
Once IETF grant offer is received: contractor appointment (G99 accredited contractor for systems above 50 kW); G99 application to DNO (submit immediately — allow 18-26 weeks for connection); construction and commissioning; Ofgem REGO registration. Grant claim process: DESNZ disburses grant in arrears of project completion; you submit invoices, commissioning certificates, MCS certificate, and generation meter readings; grant paid within 4-6 weeks of verified claim. Total timeline from EoI to energised system: typically 12-18 months.
UK warehouse solar economics 2026 — at a glance
UK commercial solar PV for warehouses has fundamentally changed economically between 2019 and 2026. Three structural shifts drive current 4-6 year paybacks: grid electricity has nearly doubled from 12-15p/kWh blended day rate in 2019 to 16-26p/kWh in 2026, with peak Time-of-Use rates now reaching 28-35p/kWh during 16:00-19:00 evening peak; battery system cost has fallen from £700-£900/kWh installed in 2020 to £250-£450/kWh in 2026; and 100% Annual Investment Allowance up to £1m of capex per year delivers immediate 25% corporation tax relief on solar capex. A typical 1 MW warehouse rooftop solar install costs £700,000-£800,000, generates 870,000-950,000 kWh per year, displaces £155,000-£180,000 of grid electricity annually, and pays back in 4-5 years before tax — 3-4 years after AIA tax shield.
Compliance pressure driving warehouse solar adoption in 2026
Four converging UK compliance forces make warehouse solar effectively necessary by 2030. (1) MEES EPC B by April 2030: all commercial property must achieve EPC rating B or better to be let. Solar PV adds 5-15 EPC points and is often the most cost-effective compliance route for warehouse stock currently at EPC C-D. (2) ESOS Phase 4 (December 2027 deadline): Energy Savings Opportunity Scheme requires large UK businesses to commission energy audits and implement or document rationale for solar recommendations. (3) SECR reporting: mandatory Streamlined Energy and Carbon Reporting requires Scope 1+2 emissions disclosure in annual reports — solar PV directly reduces reported Scope 2 figure. (4) Customer Scope 3 mandates: Amazon Climate Pledge, Tesco Net Zero, M&S Plan A, Sainsbury's Plan for Better, John Lewis Net Zero, JLR/Stellantis Tier-1 supplier programmes all flow Scope 3 supplier requirements through contract weighting and CDP/EcoVadis reporting. 3PL operators and owner-occupied warehouses serving these customers face direct commercial consequences if they fail to demonstrate verifiable renewable generation by 2027-2030.
How we model warehouse solar — half-hourly meter data, not assumptions
Every warehouse solar feasibility we deliver starts with your 12 months of half-hourly meter data and a roof drawing. Standard online solar calculators use generic per-sqft estimates that miss the operational pattern variation driving 30-40% of total payback difference. Our methodology: PVSyst yield model calibrated for your specific roof orientation, tilt and shading; self-consumption profile derived from your actual half-hourly demand at 15-minute resolution; 25-year DCF with monthly cashflow granularity; capital allowance schedule (AIA + ECA where applicable); grant funding scenario where eligible (IETF Phase 3 for manufacturers above 1 GWh/yr); SEG export tariff and REGO income; O&M cost schedule; sensitivity analysis on grid tariff inflation, self-consumption ratio, capex per kW and discount rate. Output: simple payback, after-tax payback, IRR, NPV at 4%/6%/8% discount rates, and 25-year cumulative return. If the numbers do not work for your specific site, we say so — we have walked away from over 60 projects since 2020 where economics did not justify proceeding.
Get a free desk feasibility — 7 working days
Send us 12 months of half-hourly meter data and a roof drawing (PDF or DWG). Within 7 working days we deliver: indicative system size from PVSyst modelling of your specific roof; financial DCF showing payback, IRR and NPV under three financing routes (outright purchase, asset finance, PPA); customer Scope 3 audit pack template for your supply chain context; grant funding eligibility assessment (IETF, UKSPF, Enterprise Zone ECA, Freeport ECA); DNO connection cost estimate from grid heatmap; structural pre-assessment from drawings; honest assessment of whether your site suits solar. No charge, no obligation. Call +44 7707 970 661 to discuss, or send your meter data to info@solarpanelsforwarehouses.co.uk — quote within 7 working days, guaranteed.