Commercial Solar Grants & Incentives UK 2026

There is no single cash grant for commercial solar in the UK — but the combination of AIA tax relief, SEG export payments, and sector-specific grant schemes means most commercial businesses recover 30-50% of their investment within the first two years through tax savings alone. This guide covers every incentive available in 2026.

Complete Grant and Incentive Summary (2026)

Annual Investment Allowance (AIA): Your Biggest Incentive

The Annual Investment Allowance is not a grant — it is a tax deduction — but for most commercial solar buyers it is more valuable than any grant because it is immediate, certain, and requires no competitive application.

How it works: In the year you install commercial solar, you can deduct 100% of the capital cost from your taxable profits. This reduces your Corporation Tax or Income Tax bill by an amount equal to your tax rate × system cost.

Examples:

• 25% CT rate + £75,000 system = £18,750 tax saved in year 1
• 25% CT rate + £200,000 system = £50,000 tax saved in year 1
• 19% CT rate (smaller company) + £75,000 = £14,250 tax saved

What qualifies: Solar panels, inverters, mounting systems, cabling, monitoring equipment, battery storage, and EV chargers are all qualifying plant and machinery. DNO connection costs may also qualify if treated as capital expenditure.

Sole traders and partnerships: Claim the equivalent through Capital Allowances (boxes 35-56 on the Self Assessment Tax Return). The same 100% first-year deduction applies.

Timing: You claim in the tax year the asset is first brought into use. For a system commissioned in January 2026, you claim on the 2025/26 return. Check with your accountant on the optimal timing if you are near a year-end.

AIA limit: £1,000,000 per year per business. A group of companies shares one AIA limit.

For a full AIA guide including examples and how to claim, see our AIA Solar Guide.

Smart Export Guarantee (SEG): Getting Paid for Surplus Solar

The Smart Export Guarantee requires licensed electricity suppliers with 150,000+ residential customers to offer a tariff for surplus solar electricity exported to the grid. MCS certification is mandatory — systems without an MCS certificate cannot register for SEG.

Rates as of May 2026. You must use your current electricity supplier for SEG. If your supplier is not listed, they may still be obligated to offer SEG if they have 150,000+ customers. MCS certificate required at application.

How to maximise SEG income: Most commercial solar systems self-consume 70-85% of generation. The 15-30% that is exported earns SEG income. A 100kW system generating 100,000 kWh/year with 20% export (20,000 kWh) earns £600-£1,200/year at current rates. This is modest compared to the £25,000+ in bill savings but is income for electricity you would otherwise give away for free.

Export limiting: Some DNOs impose export limits (e.g., max 16kW export from a 100kW system). If your G99 has an export limit, you can still claim SEG on whatever you are permitted to export. Octopus Energy and OVO do not penalise for constrained export.

Industrial Energy Transformation Fund (IETF) Phase 3

The IETF is a Department for Energy Security and Net Zero (DESNZ) grant scheme for energy-intensive industrial businesses. Phase 3 is open to manufacturing, food processing, automotive, chemicals, glass, ceramics, cement, and data centre sectors.

• Grant level: 30-50% of eligible capital costs for small/medium businesses; 25-35% for large businesses
• Minimum project size: £100,000 of eligible capital expenditure
• Eligible technologies: Solar PV, battery storage, heat pumps, waste heat recovery, electrification of heat, hydrogen-ready equipment
• Application process: Competitive — requires energy audit, implementation plan, and business case. Applications assessed quarterly.
• Where to apply: gov.uk/guidance/industrial-energy-transformation-fund

Solar PV is most compelling as part of an IETF project when combined with battery storage or process electrification — this increases the total eligible cost and strengthens the energy savings case.

Public Sector Decarbonisation Scheme (PSDS) Phase 5

The PSDS provides capital funding to public sector bodies for low-carbon energy and heat projects. Phase 5 runs 2025-2028.

• Grant level: 50-70% of eligible costs (higher for NHS trusts and schools)
• Who qualifies: NHS trusts, local authorities, schools, universities, housing associations, emergency services, and other public bodies
• Eligible costs: Solar PV, heat pumps, LED lighting, building fabric improvements, battery storage
• Application: Submit via the PSDS portal — requires a qualified energy auditor assessment
• Timeline: Grant awards typically announced within 3-4 months of application round close

Schools have benefited most from PSDS — a typical 50kW school solar system costing £38,000 can attract a £20,000-£27,000 PSDS grant, reducing payback to under 2 years.

Business Energy Scotland (Scottish Businesses)

Scottish businesses have access to additional support not available in England and Wales:

• Business Energy Scotland (BES) — run by Zero Waste Scotland, provides free energy audits and specialist advice for Scottish SMEs investing in energy efficiency or renewables
• Scottish Enterprise SME Loan — flexible loan funding for Scottish SMEs including for renewable energy projects
• CARES (Community and Renewable Energy Scheme) — up to £200,000 loan at 5-8% for community-owned renewable energy projects in Scotland
• Zero Waste Scotland grants — periodic grant programmes for circular economy and energy efficiency projects including solar

See our full Scotland commercial solar guide for details on Scottish-specific grants and DNO requirements.

Zero VAT on Commercial Solar (Since April 2022)

All solar panel installations in the UK are zero-rated for VAT since April 2022. This includes:

• Solar panels (supply and installation)
• Inverters and monitoring equipment
• Battery storage systems (when installed with solar)
• EV charge points (when installed with solar)
• Solar thermal systems

Zero-rating means 0% VAT at point of sale — you do not pay 20% and then reclaim it. For a £75,000 commercial solar system, zero VAT saves £15,000 compared to standard-rated supply.

ESOS Phase 4: Solar as a Compliance Tool

The Energy Savings Opportunity Scheme (ESOS) requires all UK businesses with 250+ employees or £44M+ turnover to conduct energy audits every 4 years. Phase 4 compliance deadline is December 2027. Solar installations identified in an ESOS audit are classed as qualifying actions. Businesses with audit-identified solar projects can use the ESOS process to fast-track internal capital approval. MCS installers can provide the necessary documentation confirming that an installation meets ESOS audit recommendations.

How to Claim: Checklist

1. Get your solar installation quoted and contracted with an MCS certified installer
2. Commission the system and receive your MCS certificate
3. Install a smart meter (required for SEG) — your electricity supplier or installer can arrange
4. Apply for SEG with your electricity supplier (online, takes 10-15 minutes)
5. Inform your accountant of the installation date and cost for AIA claim in the current tax year
6. If industrial (IETF) or public sector (PSDS): contact your relevant scheme administrator before installation — grants must be pre-approved and cannot be claimed retrospectively

Frequently Asked Questions

Related Guides

• Annual Investment Allowance — Full Solar Guide
• IETF Phase 3 Grant Guide
• PSDS Phase 5 Grant Guide
• Commercial Solar Panel Costs 2026