What the IETF was
The IETF was a government capital grant for high energy users in England, Wales and Northern Ireland, funding energy-efficiency and deep decarbonisation projects on industrial sites. Grants typically covered 30–50% of eligible costs, and Phase 3 set a minimum grant of £75,000 for smaller businesses.
Where the scheme stands
There is no Phase 4. In July 2025 the government confirmed that the planned second window of Phase 3 would not go ahead, and no successor scheme has been announced. Projects already awarded funding are still being delivered, but new applications are not being accepted. In Scotland, the separate Scottish Industrial Energy Transformation Fund (SIETF) runs its own windows.
Who it was for
The IETF was aimed at manufacturing and other energy-intensive industrial sites, with eligibility set by sector and site energy use. Most commercial solar buyers — offices, warehouses, retail, farms — were never eligible.
What applications involved
Applications needed detailed engineering and financial evidence — an energy and carbon baseline, a savings forecast, a delivery programme, quotes and a financial case — which is why most applicants used specialist consultants. The same evidence is still worth preparing: it is what a lender, an asset-finance provider or a board will want to see.
How it was scored
Rounds were competitive, with applications assessed on value for money in carbon saved, deliverability and wider benefits — so even a strong application was not guaranteed funding.
How manufacturers fund solar now
Without the IETF, the numbers for industrial solar rest on tax relief and finance. The Annual Investment Allowance gives 100% relief in year 1 on up to £1m of spend a year (companies can claim a 50% first-year allowance on special-rate spend above that), asset finance spreads the cost, and a PPA removes it. For a site with steady daytime load, solar often pays back without a grant.
Timeline reality check
A grant-funded industrial project typically took a year or more from application to commissioning. Without a grant, a commercial rooftop system can usually move from survey to installation much faster — the main variable is the DNO connection approval.
What to do now
If you were planning around the IETF, start from your half-hourly data: KMM models capex with AIA, asset finance and a PPA side by side for your site, and flags any grant that is actually open when we build the proposal.
