2026 Update: PSDS & IETF closed. AIA gives 100% year-one relief on solar. 2026 active stack still delivers 40–60% effective subsidy. See 2026 grants →

FAQs

UK commercial solar grants — questions we get most.

They're grouped here by topic so you can skim. If yours isn't covered, the free funding review will get a written answer back to you by email.

Looking for the detail? Start with the full guides
On this page
  1. 01Solar basics — installation, maintenance, lifespan
  2. 02Eligibility & qualification
  3. 03Specific grant schemes
  4. 04Tax allowances & finance
  5. 05Process & timelines
  6. 06Operations, exports & risk

Solar basics — installation, maintenance, lifespan

The practical questions that come up most about commercial solar before the funding conversation starts.

How much can I save with commercial solar grants?
Grants and tax benefits typically cover 20–50% of installation costs. Example: a £400,000 solar project using the Annual Investment Allowance alone effectively costs about £300,000 at 25% corporation tax. The IETF closed in July 2025 and never funded solar PV. A £100,000 system using the Annual Investment Allowance alone effectively costs £75,000. PSDS-funded public sector projects can be 100% covered. We model exact figures during the free funding review.
How long does a commercial solar installation take?
Most commercial installations take 1–3 weeks of on-site work depending on system size. A typical 100 kWp system takes 5–7 working days; larger systems (500 kWp+) typically 2–3 weeks. We schedule around your operations to minimise disruption — most work is on the roof with brief electrical shutdowns (1–4 hours) at convenient times.
Will installation disrupt my business?
Minimal disruption. Most work is on the roof and doesn't affect operations below. Electrical shutdowns are brief (1–4 hours) and scheduled at convenient times, often evenings or weekends. Most clients report barely noticing the installation process beyond the rooftop activity.
What if my roof needs repairs or reinforcement?
Structural surveys identify any required works before installation. Roof remediation can be included in the project scope and costs may be partially covered by some grants (PSDS allows roof remediation when it's part of an integrated decarbonisation package; private-sector grants typically don't). Modern panels are lighter than older systems and most commercial roofs built post-1990 take PV without reinforcement.
How long do commercial solar panels last?
Tier 1 modules carry 25–30 year linear performance warranties. In practice good systems are still producing 85% of nameplate output at year 30. Inverters last 10–15 years and are replaced once during the system lifetime (typically year 12–15). The financial model treats panels as a 25-year asset with ~0.5% annual degradation.
What maintenance is required?
Annual visual inspection, electrical test every 3 years, occasional cleaning (rain naturally cleans panels in most cases). Inverter replacement at year 12–15. Budget £8–£15/kWp/year for full O&M with monitoring. Most projects bundle 2 years of O&M into the install contract.
How much roof space do I need?
Roughly 5–6 square metres per kWp installed. A 100 kWp system needs around 550 m² of usable roof; a 500 kWp system needs 2,800 m². Roof should be in reasonable condition, relatively unshaded, ideally south, east or west facing. We assess feasibility during email review.
What if my roof isn't suitable?
Alternatives exist — ground-mounted systems on adjacent land, solar canopies on car parks, wall-mounted installations, or sleeved off-site PPAs (where solar is generated remotely and contractually allocated to your supply). We explore all options during the assessment. Sometimes multiple smaller installations across different buildings work better than one large array.
Are planning permissions needed?
Most commercial solar installations are permitted development and don't need full planning permission. Exceptions include listed buildings, conservation areas, systems facing highways, sites near airports (glint and glare assessment), and ground-mount installations above 1 MW. We handle all permissions and work with local authorities on your behalf.
Do I need to own my building?
Ownership is ideal but not essential. Long-term leases (15+ years remaining) work for most PPA structures. Some landlords welcome solar as it increases property value — landlord-funded structures with the tenant signing a long-term off-take agreement are increasingly common. We can help negotiate agreements that benefit both parties.
Will solar panels increase my property value?
Yes. Commercial properties with solar typically see 3–5% value increases and are more attractive to buyers and tenants. Solar demonstrates environmental commitment, reduces operating costs for the next occupant, and supports certifications (BREEAM, Net Zero Carbon Buildings Standard) that command rental premiums.
How much CO2 will my business save?
A typical 100 kWp system offsets 40–50 tonnes of CO2 annually, equivalent to planting 2,000+ trees each year. Over 25 years, that's 1,000–1,250 tonnes of CO2 prevented. Larger systems achieve proportionally greater environmental impact. Solar is one of the most effective ways to reduce Scope 2 (purchased electricity) emissions.
Are solar panels recyclable?
Yes — modern Tier 1 panels are 95%+ recyclable. Most manufacturers operate take-back schemes. The aluminium frames, glass, copper and silicon can all be recycled. The UK solar industry has robust end-of-life recycling infrastructure in place.

Eligibility & qualification

Who qualifies for which scheme — sector eligibility, ownership structure, the practical tests assessors apply.

Are commercial solar grants still available in the UK in 2026?
Some routes remain, but the headline schemes have closed: IETF Phase 3 and PSDS Phase 4 are closed to new applications and the Rural England Prosperity Fund ended in March 2026. What remains is mainly tax relief (the Annual Investment Allowance reimburses 25% of solar capex via corporation tax for any UK incorporated business, which often beats a grant on net economics), plus the Smart Export Guarantee, PPAs, Salix loans for the public sector and the devolved-nation schemes. Check each scheme current status before relying on it.
Can a private limited company get a solar grant?
There is no direct cash grant route: the IETF, which covered industrial sites, closed in July 2025 and never funded solar PV. For everyone else, the Annual Investment Allowance (100% first-year tax relief) acts as the de facto grant; rural businesses can also access REPF; and PPA structures provide third-party-funded solar with no grant needed. Most non-industrial commercial sites end up on a AIA + PPA stack.
Does my business have to be UK-owned?
No. The funder requirement is that the project is delivered in the UK and the applicant is UK-registered (a UK company or branch). Foreign-parented UK subsidiaries qualify for the Annual Investment Allowance; the IETF closed in July 2025 and takes no applications.
Are sole traders and partnerships eligible?
They are eligible for Annual Investment Allowance and REPF, but not for the Annual Investment Allowance (which is corporation-tax-only). For grant purposes, partnerships often need to demonstrate that the project entity has separate accounts. The IETF closed in July 2025 with no successor, so it is not a route for sole traders or any other business.
Do listed companies face different rules?
They face the same eligibility, but PPA structures need careful IFRS 16 review — some PPAs are now treated as right-of-use assets and brought back on balance sheet. The funding mechanism matters less to listed companies than the accounting treatment.
Are charities eligible for commercial solar grants?
Charity solar projects cannot use the IETF: it closed in July 2025 with no successor and never funded solar PV. REPF, which ended in March 2026, was open to charities operating in rural areas. Tax allowances do not apply (no corporation tax). The right answer for most charities is normally a PPA or grant funding from charitable foundations.
Are housing associations eligible?
Generally no. Housing associations sit outside PSDS eligibility and IETF sector restrictions. They have separate routes via the Social Housing Decarbonisation Fund (SHDF) which is residential-focused and not directly comparable to commercial solar grants. We can advise on commercial properties held by housing associations (offices, depots) but not residential stock.

Specific grant schemes

The closed schemes (IETF, PSDS, REPF) and what replaced them: the questions that come up most about each.

What was the closed IETF, and did it fund solar?
The Industrial Energy Transformation Fund was a DESNZ programme for energy-intensive industry. Its last window shut on 19 April 2024 and it closed in July 2025 with no successor. Solar PV and other electricity generation were never eligible.
Can we apply for IETF funding, now that it has closed?
No. The fund closed in July 2025, the planned second Phase 3 window was cancelled and no successor is planned. Only projects already awarded continue, to March 2028.
Did the closed IETF fund battery storage?
No. Batteries were never an eligible IETF technology and the fund is closed. Battery storage now rests on capital allowances, finance or a PPA.
Who could apply for PSDS Phase 4?
PSDS Phase 4 closed in November 2024. When it ran, eligible applicants were NHS trusts, local authorities (district, county, unitary, combined), state-funded schools and academies, FE colleges, central government departments and arms-length bodies, fire and police services. Universities were mostly outside (they have their own LCSF route). Charities and housing associations were not eligible.
Why does PSDS require a Heat Decarbonisation Plan?
PSDS scores integrated retrofits, not individual measures. The HDP is the document that proves your solar PV fits inside a credible whole-estate plan to remove fossil heat. Solar without an HDP almost always loses scoring.
How long does Salix take to award a PSDS grant?
4–6 weeks after window close in normal cycles. Phase 4 has been running on time. Awards are typically announced as a batch — be ready to draw down within 3 months of award.
Can private contractors deliver PSDS-funded work?
Yes, that is how almost all PSDS work is delivered. The applicant is the public sector body but procurement runs to standard public-sector frameworks (Crown Commercial Service, ESPO, NEPO).
What is REPF and who administers it?
The Rural England Prosperity Fund is a DEFRA programme delivered through local councils. It covers up to 40% of capex on rural enterprise capital projects including solar PV. Each council has its own allocation and scoring weightings. Application narratives that anchor on rural growth outcomes (jobs, contract revenue, GVA) score better than pure decarbonisation pitches.
Did the IETF apply outside England? It covered England, Wales and Northern Ireland but not Scotland, which had the separate SIETF; both funds are now closed.
No. Scotland had its own SIETF, which closed in March 2025. (The IETF did cover Wales and NI, so the answer should be ”Not in Scotland”.) Wales has the Welsh Industrial Decarbonisation Fund. Northern Ireland operates separate routes through the Department for the Economy. The eligibility criteria are similar but the application processes and timetables differ.

Tax allowances & finance

Annual Investment Allowance, AIA, PPAs and asset finance — the funding routes that don't go through grant applications.

How much does the Annual Investment Allowance actually save?
Annual Investment Allowance gives you 100% first-year capital allowances on qualifying plant, including solar PV and battery storage. For a company paying main-rate corporation tax (25%), that means 25p back on every £1 of capex — claimed on the corporation tax return for the period the capex is incurred. A £400k system saves you £100k in corporation tax.
Is solar PV "main pool" plant or "special rate"?
Special rate. HMRC designates all capital expenditure on the provision of solar panels as special rate expenditure (Capital Allowances Manual CA22335, in force since 1 April 2012), so the array and its associated plant sit in the special rate pool at a 6% writing-down allowance — not the 18% main pool. That is why Full Expensing, a main-rate measure, does not reach solar. AIA is the 100% year-one route because AIA is available against special rate expenditure; above the £1m cap the 50% special rate first-year allowance applies, with the balance written down at 6%.
Can we use AIA and the 50% special rate allowance together?
Yes — across one project, though not twice on the same pound of spend. AIA gives 100% relief on the first £1,000,000 of qualifying expenditure per group per year. Spend above that cap attracts the 50% special rate first-year allowance, with the remaining balance entering the special rate pool at a 6% writing-down allowance. Most commercial solar projects sit under the AIA cap, so relief is full in year one. We model both legs side by side.
What happens if we sell the solar plant later?
A balancing charge — broadly the lower of (sale price) or (original AIA claimed) gets added back to taxable profits in the year of sale. For solar this rarely matters; PV is sold as part of a building sale, where capital allowances transfer to the buyer.
How do Power Purchase Agreements work?
A third-party investor pays for and owns the solar PV asset. You, the site host, sign a long-term contract (15–25 years) to buy electricity from them at a fixed pence/kWh rate. The PPA rate sits 6–9p/kWh below grid prices for typical UK commercial sites in 2026.
What's the catch with a PPA?
Two things. First, the rate escalator — most PPAs include 1.5–3% annual escalation, often linked to RPI or CPI. Over 25 years that adds up. Second, the exit terms. Selling the building or vacating the site mid-PPA typically triggers a buyout — make sure the buyout schedule is in your favour from year 7 onward.
Can a PPA be combined with a grant?
Yes. The PPA funder can take the grant on your behalf and pass through a lower headline tariff. This was seen on some earlier IETF projects. The IETF closed in July 2025, never funded solar PV, and offers no grant today.
What if we want to buy out the PPA later?
Most PPAs include a buyout schedule from year 7 or 10. Typical buyout values are 75–85% of fair market value at the buyout date. We always negotiate caps on the buyout multiple.

Process & timelines

How long applications and projects actually take, what to do if rejected, and the most common mistakes.

How long does a UK solar grant application take to prepare?
Neither the IETF (closed July 2025, no successor planned) nor the PSDS is open, so there is no application to prepare; plan on tax relief and finance. The funder then takes 8–12 weeks to score. Total from kickoff to grant decision: 16–22 weeks.
Can the application be done in parallel with the install design?
Yes, and it usually is. The application requires a detailed design, supplier quotes and financial model — those documents are also what the installer needs. We sequence the work so the same outputs feed both streams.
What happens if we get rejected?
Rejection feedback usually identifies one or two scoring weaknesses. Depending on the funder, you can resubmit in the next window with a strengthened application. IETF applications can no longer be made or resubmitted: the fund closed in July 2025, the planned second Phase 3 window was cancelled and no successor is planned.
Can we start the install before grant approval?
No. All UK solar grants require the project to be unstarted on the day the application is submitted. Spend incurred before that date is not eligible. This is a hard rule and is the most common reason grants are clawed back.
What is a Heat Decarbonisation Plan and how long does it take?
A Heat Decarbonisation Plan (HDP) is required for most PSDS Phase 4 applications. It is a structured technical assessment of how an estate will move off fossil heat. Typical HDP development is 4-8 weeks per estate, including Stage 4 RIBA-equivalent surveys, IES VE-equivalent modelling, and phased capex scheduling.
How long does build typically take after grant award?
12-16 weeks for sub-1MW commercial rooftop projects. Larger projects (1MW+ or ground-mount) typically take 16-24 weeks. The DNO connection is usually the long pole — G99 turnaround is 60-110 working days depending on region. IETF and PSDS are closed to new applications, so a new project has no grant milestones; plan the timeline around the DNO connection.

Operations, exports & risk

Smart Export Guarantee, ongoing maintenance, insurance, subsidy control and clawback risk.

Will my solar panels still pay back if energy prices fall?
Probably yes, but more slowly. Most commercial PV models assume 6–9% wholesale energy inflation; if grid prices flatline at £160/MWh for the next decade, payback periods extend by 12–18 months. With the Annual Investment Allowance or a grant, the project still beats most other capex options on IRR.
How do I claim Smart Export Guarantee?
You contact a SEG-licensed supplier (Octopus, EDF, E.ON Next, Scottish Power, etc.), provide your MCS certificate and meter point details, and switch your export contract. Payments come monthly or quarterly against your half-hourly export readings. You can hold import with one supplier and export with another.
Do solar panels need maintenance?
Yes — annual visual inspection, electrical test every 3 years, inverter replacement at year 12–15. Budget £8–£15/kWp/year for full O&M with monitoring. Most projects bundle 2 years of O&M into the install contract.
How long do commercial panels last?
Tier 1 modules carry 25–30 year linear performance warranties; in practice good systems are still producing 85% of nameplate output at year 30. The financial model treats panels as a 25-year asset with ~0.5% per annum degradation.
What insurance do we need on a solar PV install?
Three things: contractor's all-risk during install (provided by installer), insurance-backed warranty for the post-install period (provided through MCS-aligned schemes), and your standard property insurance updated to declare the asset. Insurance-backed warranty is non-negotiable for grant-funded projects.
Are there subsidy control issues post-Brexit?
Yes — the UK Subsidy Control Act 2022 replaced EU state aid. For solar grants the practical rule is "no double-funding". You cannot stack two grants from different government programmes for the same plant. You can stack a grant with tax allowances and SEG.
What happens if we breach grant conditions?
Clawback. The funder can demand return of the grant plus, in some cases, interest. Common breach causes: project not completed on time, asset sold within the qualifying period, monitoring data not provided. We build the grant compliance schedule into the project plan from day one.
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Funding by asset class

The allowance depends on the asset, and most pages on this topic get it the wrong way round. Solar PV is special-rate expenditure (HMRC Capital Allowances Manual CA22335), so the 100% year-one route is the Annual Investment Allowance — Full Expensing is a main-rate measure and does not reach it. Battery storage, EV charging and heat pumps are Heat pumps for space or water heating are special-rate: AIA, then the 50% FYA. Standalone batteries are probably main-rate (full expensing for companies), but HMRC has no specific guidance; confirm with your adviser.

Free funding review

Find out which 2026 schemes your site actually qualifies for

What you get
  • 1. A short written funding note naming every scheme your site qualifies for in 2026 — and the ones it does not.
  • 2. Indicative system size and a capex band for your roof.
  • 3. Year-one tax treatment per asset in £ — solar is special-rate expenditure, so the route is the Annual Investment Allowance; heat pumps for building heating are also special-rate integral features, and standalone battery storage is probably main-rate plant (HMRC has no specific guidance, so confirm with your adviser). Most pages get this the wrong way round.
  • 4. Projected SEG export revenue at current rates.
  • 5. Any red-flag eligibility or DNO issues we can see up front.

Covers solar PV, battery storage, EV charging and commercial heat pumps — separately or as one bundled project. If your project is a heat pump or a battery rather than a roof, say so in the message box and the note is written against that asset instead.

What we will not do
  • · We do not pass your details to multiple installers.
  • · We do not run a lead auction, and your phone number is optional.
  • · No marketing lists, no unsolicited calls.
  • · We are an independent funding information service — not an installer.

Five questions. They are the eligibility test itself — scheme eligibility in 2026 turns on sector, tenure, site size and spend, so we cannot shortlist anything without them.

We reply from funding@commercialsolargrants.co.uk. A phone number is not required.

Explore this guide cluster

Commercial solar grants & funding

Every active 2026 route to fund commercial solar — grants, tax allowances and loans — with the eligibility and application detail behind each.

Pillar guideCommercial solar grants & incentivesThe master guide to what is open and closed in 2026.