Ymestyn grant: guidance

This guidance has been provided alongside an application form for the Ymestyn Grant.

The Ymestyn Grant is a Welsh Government fund supported by Great British Energy.

This grant has been set up to unlock locally-owned renewable energy projects and in particular to enable completion of more financially challenging projects by providing ‘top-up’ funding to improve financial paybacks. This grant funding can be used in conjunction with other Welsh Government funding, such as the Wales Funding Programme.

The funding is available to all public sector bodies and community groups in Wales and can support building-connected and grid-export renewable energy projects which are ready for implementation. 

Capital grants will be provided to support projects which can be implemented and fully commissioned by 30 November 2026. 

Ymestyn complements other Welsh Government funding support, including:

• Wales Funding Programme: low-interest loans for public sector decarbonisation
• Ynni Cymru: for multi-technology smart local energy systems
• Development Bank Wales: local energy funding support for community enterprises

The objectives of the Ymestyn Grant are:

• to unlock financially challenging renewable energy projects
• to support locally-owned renewable generation
• to work alongside other funding sources and unlock these for projects not currently meeting the required criteria
• to fast-track projects in order to see locally-owned generation come on online by Autumn 2026

The key criteria of the Ymestyn Grant are as follows:

• open to all Welsh public sector organisations and community enterprises
• supports ambitious renewable energy projects with challenging financial cases above a 10-year payback
• A 40% maximum capital intervention with a minimum threshold of 10% (for large projects where 10% of capital costs is a significant value, below 10% grant value projects may be considered)
• projects must be completed and commissioned by 30th November 2026

The grant is open to projects developed by public sector organisations and community enterprises, but not to projects developed by or in conjunction with commercial enterprises. 

Example technologies which can be supported are: 

• rooftop PV
• solar canopies
• ground-mounted solar PV
• wind turbines
• hydropower
• battery energy storage systems ('behind the meter') where these are in conjunction with renewable energy projects

These can be: 

• site-based renewable generation connected 'behind the meter' including those with partial grid export
• private-wire renewable energy projects to any off-taker in Wales
• grid-export renewable energy projects  

Projects which cannot be supported include:

• stand-alone battery energy storage systems
• renewable heat projects (including renewable CHP projects)
• existing funded projects (unless additionality can be evidenced) 

Projects need to be ready for implementation and eligible costs are any capital costs associated with project installation including enabling civil works or grid connection costs. 

Note that the Ymestyn fund is in place to support ambitious renewable projects and on this basis, we expect projects to include an element of the following to be considered as ambitious renewables: solar canopies, battery energy storage, offsite private wires, hydro/wind, grid connected renewables. We may consider other renewable projects without these elements with justification in the application detail.

Costs which cannot be claimed include: 

• internal salaried staff costs
• recoverable VAT, applicants will need to manage this cash flow aspect appropriately where VAT is paid in one financial year but recovered the next. Note: we expect all VAT to be recovered
• operation and maintenance costs (i.e. multi-year capitalised upfront not allowable) 

Project spend and project completion must be by 30 November 2026.

Where full project completion by this date will be challenging, we welcome applications for distinct phases of larger projects which can be commissioned and producing power by this date. 

Community Energy Enterprise (definition)

A community energy enterprise is a community‑led organisation that develops, owns, or manages energy projects and services for the public benefit. It operates on a not‑for‑profit or social enterprise basis, prioritising social, environmental, and local economic outcomes, and reinvests any surplus into the community. Eligible legal forms typically include Community Benefit Societies, Cooperative Societies, Community Interest Companies, Charitable organisations (or wholly‑owned subsidiaries thereof), and Companies Limited by Guarantee, provided their governing documents commit to community benefit, democratic governance, and responsible financial management.

The grant is available to support ambitious projects with simple payback of longer than 10 years. The scale of grant available will be proportionate to the payback gap above 10 years.

Worked example: a project with a 12.5-year payback will receive 2.5/12.5 = 20% grant of total capital costs, up to a maximum of 40% of total eligible capital costs for the project (and a minimum threshold of 10%). 

Projects which are calculated to already have a simple payback lower than 10 years will not be eligible for the grant. 

Ymestyn will accurately calculate payback to ensure a fair allocation of grant, the application form will consider the following in payback calculation:

• forecast average 10-year tariff, including site import, grid export, and any private wire PPA tariffs
• expected average export tariffs or any agreed private wire PPA tariffs, considering inflation over a 10-year period
• investment costs including Principal Contractor, Client Engineer, DNO, and other specialists
• non-domestic rates (business rates), if applicable
• operation & maintenance, and performance management costs

Note that contingency costs will not be used in the payback calculation.

The window for applications is 19 December 2025 to 6 February 2026 inclusive. We may close or extend the application window depending on the volume and scale of applications received. 

Please make an application using the Excel form provided and send by e-mail to Ymestyn.grant@energyservice.wales.

Each form allows for up to 15 sites to be applied for. Up to two applications may be submitted per organisation. We ask that applicants express any priority sites in the detail.

Please submit evidence to support your application. These should include, where applicable:

• design documents or Investment Grade Proposal
• status of planning application and e.g. Sustainable Drainage System (SUDS) approval where applicable
• grid connection offer status
• evidence of costs e.g. supplier quotations
• evidence of current tariffs (day/night/export/PPAs) 

These should be emailed alongside your application form. 

Submitted application forms must have all relevant sections complete and supporting information attached. Failure to do so may result in your application being rejected. 

Clarification meetings may be required with applicants. These may occur anytime during the grant scheme.

Applications will first be assessed on their eligibility and financials. 

Payback and minimum and maximum grant value will be assessed on a site-by-site basis.

Organisations will be required to submit project financial information including CAPEX and OPEX costs, power export arrangements and electricity tariffs. These will be used to calculate simple financial payback and the associated grant value. The values submitted will also be assessed using value for money checks to ensure costs are considered reasonable according to industry benchmarks. The follow metrics will be considered in assessment:

• £/kW checks on overall cost including install for type of renewable project (e.g. solar canopy, standalone)
• £/kW checks on price for solar panel supply
• £/kWh battery supply
• kW of renewables capacity to battery kWh ratio
• electricity tariff checks

Organisations will be required to confirm the percentage of on-site consumption in order to inform payback calculations and to provide evidence of energy modelling to back this up. 

In addition to the financial checks, the projects will be assessed on their ability to achieve completion by November 2026. 

This will be assessed based on the strength of the project plan and the status of the following key project milestones:

• detailed design completed
• planning permission status, if required, or confirmed as a permitted development by the local planning team
• procurement position, whether suppliers are in contract
• grid connection
• Sustainable Drainage System (SUDS) approval (if required e.g. for solar canopies)

For public sector organisations which are also seeking funding from the Wales Funding Programme, it is expected that they will apply for both the Wales Funding Programme and Ymestyn concurrently for a split of funding between loan and grant.

Two separate application forms are required, however, the details and supporting evidence will be similar for each.

For some projects, in particular those with high export income, we recognise that Ymestyn and Wales Funding Programme will vary in their payback calculations. We recommend applicants complete the Ymestyn application form first to determine the potential grant value, and then complete the Wales Funding Programme application for the remaining value required of loan. We recognise that for these projects the Wales Funding Programme payback and carbon criteria may not be met, but we encourage that these applications are progressed for consideration.

The number of projects requesting funds from both Ymestyn and the Wales Funding Programme should match. Please don't add additional projects to one or other of the loan or grant applications. This will allow for easier assessment of the loan / grant mix. Where a renewables programme includes further sites which are eligible only for the Wales Funding Programme (i.e. < 10-year payback), these can also be applied to the Wales Funding Programme in a second application. We note this approach will impact the compliance criteria on each application; this will be taken into consideration in assessment. 

Further details on the Wales Funding programme can be found here: The Wales Funding Programme | Salix Finance. For any enquiries, please contact Salix at wales@salixfinance.co.uk.

We request that applications to Ymestyn and Wales Funding Programme are submitted at the same time, and by copy to each other. Please submit Wales Funding Programme applications to wales@salixfinance.co.uk and Ymestyn applications to Ymestyn.grant@energyservice.wales. The Energy Service and Salix will work together to review the applications, streamline clarification queries and calls, assess the requested funding split, and progress funding approvals.

If successful, a notification award will be sent and following this a Grant Offer Letter will be issued. 

The Grant Offer Letter should be signed within 10 days of its receipt. To accept the grant, an appropriately senior person will need to sign the letter and provide bank details. 

Money can be spent from the date of the initial notification of award.

To receive the grant, applicants must provide the Energy Service with proof of quotation and contractor appointment.

There will be requests for progress reports or meetings throughout the grant period. 

The Energy Service must be notified via email regarding any material changes to the approved project e.g. change in scope, deliverability within required time period, or required grant value.

Grantees are required to provide access to operational staff for interviews or surveys, respond to requests for case studies and press releases, and agree to reasonable requests to share learning and insights. This includes, but is not limited to, sharing design and performance information, supporting site visits, and sharing case study information and photos.

We expect the majority of grantees to make a single claim, however for more complex projects up to three (3) drawdowns can be made as part of your agreed grant offer. Funds should be drawn down in arrears, as and when costs are incurred. Payment requests will be made using a claim form.

Applicants must follow claiming standards specified by the Energy Service. This includes provision of PDF invoice evidence to cover 100% of the project capital costs (of which between 10 and 40% will be funded). Templates of the required claiming documents will be provided to applicants upon signing the Grant Offer Letter.

Defrayal evidence should be provided either as part of the claim submission or within 4 weeks of the grantee receiving the funding. This can for instance include remittance advice, redacted bank statement, receipted invoice.