Underground hydrogen storage demonstrator DEVEX support

Who can apply

Your project

Your project must:

• have total eligible grant funding request of between £200,000 and £750,000

• last between 6 and 12 months

• start by 1 April 2027

• end by 31 March 2028

Any organisation receiving funding must carry out its project work in the UK, intend to exploit the results in the UK, and spend most of the funding within the UK.

Projects must always start on the first of the month, even if this is a non-working day. You must not start your project until your Grant Offer Letter has been approved by Innovate UK. Any delays within Project Setup may mean we need to delay your project start date.

You must only include eligible project costs in your application. See our overview of eligible project costs.

If your project’s total eligible grant funding request or duration falls outside of our eligibility criteria, you must provide justification by email to support@iuk.ukri.org at least 10 working days before the competition closes. We will then decide whether to approve your request.

If your project does not meet our criteria and you have not requested justification approval, your application will be made ineligible and it will not be sent for assessment.

Lead organisation

To lead a collaborative project or to work alone, your organisation must be a UK registered business of any size.

More information on the different types of organisation can be found in our Funding rules.

Academic institutions cannot lead or work alone.

Project team

To collaborate with the lead, your organisation must be one of the following UK registered:

• business of any size

• academic institution

• charity

• not for profit

• public sector organisation

• research and technology organisation (RTO)

Each partner organisation must be invited into the Innovation Funding Service (IFS) by the lead to collaborate on a project. Once partners have accepted the invitation, they will be asked to login or to create an account in the IFS. They are responsible for entering their own project costs and completing their Project Impact questions in the application.

To be an eligible collaboration:

• the lead and at least one other organisation must request funding

• you must explain why you’re collaborating and how the collaboration will work

Non-funded partners

Your project can include organisations who do not claim any funding for their work on the project. Their costs will be covered from their own resources. These can include UK, EU and other non-UK organisations. Non-UK partners are permitted to carry out project work from within their home countries and exploit the results outside the UK.

Where non-funded partners have been invited to the application on IFS, their costs will count towards the total eligible project costs.

Subcontractors

Subcontractors are allowed in this competition.

Subcontractors can be from anywhere in the UK and you must select them through your usual procurement process.

You can use subcontractors from overseas but must make the case in your application as to why you cannot use subcontractors from the UK.

You must provide a detailed rationale, evidence of the potential UK contractors you approached and the reasons why they were unable to work with you. We will not accept a cheaper cost as a sufficient reason to use an overseas subcontractor.

All subcontractor costs must be justified and appropriate to the total project costs.

Number of applications

An eligible organisation can only lead on one application. Any further applications by the same organisation as lead will be made ineligible.

An eligible organisation that is leading an application can be included as a collaborator in a further two applications and if not leading, can collaborate in any number of applications.

Sanctions

This competition will not fund you, or provide any financial benefit to any individual or entities directly or indirectly involved with you, which would expose Innovate UK or any direct or indirect beneficiary of funding from Innovate UK to UK Sanctions. For example, through any procurement, commercial, business development or supply chain activity with any entity as lead, partner or subcontractor related to these countries, administrations and terrorist groups.

Use of animals in research and innovation

Innovate UK expects and supports the provision and safeguarding of welfare standards for animals used in research and innovation, according to best practice and up to date guidance.

Applicants must ensure that all of the proposed work within projects, both in the UK and internationally, will comply with the UKRI guidance on the use of animals in research and innovation.

Any projects selected for funding which involve animals will be asked to provide additional information on welfare and ethical considerations, as well as compliance with any relevant legislation as part of the project start-up process. This information will be reviewed before an award is made.

Previous applications

You cannot use a previously submitted application to apply for this competition.

We will not award you funding if you have:

• failed to exploit a previously funded project

• an overdue independent accountant’s report

• failed to comply with award terms and conditions

Innovate UK may withhold a grant payment at any time if you have any outstanding sums due to us in relation to other projects.

Subsidy control (and State aid where applicable)

This competition provides funding to enterprises using the Research, Development and Innovation Streamlined Subsidy Scheme.

The Research, Development and Innovation Streamlined Scheme can be viewed on the subsidy database here: SC10780.

This is in line with the Subsidy Control Act 2022. Further information about the Subsidy requirements can be found within the Subsidy Control Act 2022.

Innovate UK is unable to award organisations that are considered to be in financial difficulty. We will conduct financial viability and eligibility tests to confirm this is not the case following the application stage.

EU State aid rules now only apply in limited circumstances. See the Windsor Framework to check if these rules apply to your organisation.

In the ‘Project details’ section of your application you will be asked questions to indicate if State Aid or Subsidy applies to your organisation.

Further Information

If you are unsure about your obligations under the Subsidy Control Act 2022 or the State aid rules, you should take independent legal advice. We are unable to advise on individual eligibility or legal obligations.

You must not do anything which could cause a breach of Subsidy Control legislation applicable in the United Kingdom.

This aims to regulate any advantage granted by a public sector body which threatens to, or distorts competition in the United Kingdom or any other country or countries.

This award is classified as a Subsidy which does not form part of your Minimal Financial Assistance or de minimis allowance.

Funding

Up to £1.5 million has been allocated to fund project development studies in this competition.

This is subject to us receiving a sufficient number of high quality applications.

This competition is intended as the first stage of a potential wider investment of up to £10 million that UKRI has currently earmarked to support a demonstrator in this area. Any future funding would be subject to further approvals and decisions, which will be informed in part by the progress and outcomes of projects funded through this competition, including evidence of a credible and accelerated pathway to Final Investment Decision (FID). No decision has yet been made. An award under this competition does not confer eligibility for, or entitlement to, any future funding.

Funding will be in the form of a grant.

We reserve the right to adjust funding allocations for any of our competitions under exceptional circumstances, for example, in response to changes in policy, portfolio funding considerations, or broader government funding decisions.

Under the Research, Development and Innovation Streamlined Route rules, no more than £3 million can be awarded in the form of a grant to any one enterprise in any one competition.

If your organisation’s work on the project is commercial or economic, your funding request must not exceed the limits below. These limits apply even if your organisation normally acts non-economically but for the purpose of this project will be undertaking commercial or economic activity.

For feasibility studies you can get funding for your eligible project costs of:

Category 1: Feasibility studies

• up to 70% if you are a micro or small organisation

• up to 60% if you are a medium sized organisation

• up to 50% if you are a large organisation

For more information on company sizes, refer to the company accounts guidance.

If you are applying for an award funded under State aid Regulations, the definitions are set out in the European Commission Recommendation of 6 May 2003.

Innovate UK may revoke our decision to provide funding without notice if government commitment for this initiative is withdrawn.

Research participation

The research organisations undertaking non-economic activity as part of the project can share up to 30% of the total eligible project costs. If your consortium contains more than one research organisation undertaking non-economic activity, this maximum is shared between them. Of that 30% you can get funding for your eligible project costs of up to:

• 100% of your eligible project costs if you are an RTO, charity, not for profit organisation, public sector organisation or research organisation

• 80% of full economic costs (FEC) if you are an academic institution

Eligibility criteria for claiming 80% of FEC funding

1. Research organisations must use the Transparent Approach to Costing (TRAC) method as the Je-S form has now been decommissioned.

2. We pay 100% of the 80% Full Economic Cost (FEC). On IFS only enter the 80% being claimed.

To find out more see our: Cost Guidance for Academics.

Your proposal

The aim of this competition is to support the development of credible underground hydrogen storage (UHS) demonstrator projects from an early stage (FEL-1 or -2) opportunity. Projects should progress to a defined, commercially credible and materially de-risked (FEL -3 complete) investment ready proposition, capable of progressing towards final investment decision (FID) and into project execution. Successful projects must generate evidence and public learning to support cost effective UHS deployment in the UK for the electricity sector, demonstrating a discharge availability of at least 100 continuous hours.

Projects must target initial megawatt hour (MWh) scale deployment by 2030, and demonstrate a credible pathway to commercial, gigawatt hour (GWh) scale deployment in the UK by 2035.

Your project must:

• involve the proposed deployment of an UHS demonstrator facility capable of injecting, storing and withdrawing hydrogen from a subsurface environment within defined safe operating limits

• be a first of a kind development in the UK, developing a commercially viable demonstrator or prototype facility rather than a business-as-usual commercial project

• be designed and specified for hydrogen service, with a defined pathway to dedicated hydrogen storage; interim hydrogen supply or storage solutions may be considered where the applicant demonstrates it is needed to bridge hydrogen supply availability, such as challenges to near-term hydrogen pipeline connection

• propose a demonstrator facility targeting at least 10 to 100 MWh of hydrogen working gas capacity, with a credible pathway to GWh scale commercial deployment by 2035.

• be linked to one or more credible hydrogen offtake pathways, preferably including power generation applications, industrial offtake, or hydrogen transmission, distribution or storage services

• identify a specific site, and demonstrate a credible route to securing the land access, consents and permits required for construction and operation

• demonstrate that the proposed lead or team has the capabilities required to progress from the funded studies through to FID, construction and operation

If you are unable to meet any of the criteria outlined above, please provide details of what you consider your project can credibly deliver alongside any relevant justification or mitigating factors.

A technology neutral approach has been adopted within defined boundaries, recognising that there are promising UHS technologies at different levels of technical and commercial maturity.

Eligible UHS technologies include:

• engineered lined shaft

• subsurface silo or vertical pipe array

• engineered lined rock cavern

• depleted oil field

• depleted gas field

• novel salt cavern

Note: Novel salt cavern concepts will only be considered where applicants demonstrate that the proposed project involves material technical or system innovation. The project must also address defined evidence gaps and generate transferable learning additional to conventional large scale salt cavern development.

For UHS technologies not explicitly listed as eligible above, applicants may still be considered where they can demonstrate a clear case for support. This should include the potential to generate valuable project outcomes, innovation, risk reduction, public learning, or evidence that key market barriers are unlikely to be addressed through existing or anticipated policy mechanisms alone. If you believe your technology falls into this category, contact us before applying.

Project development studies

This competition is providing funding for project development studies. These are formally classified as Feasibility studies in line with Innovate UK Categories for research and development.

The studies will strengthen UHS demonstration project proposals by materially reducing the technical, commercial, consenting and delivery risks that currently prevent progression FID.

Funding is intended to deliver a measurable step change in project maturity and risk, not routine or business as usual development activity.

Priority will be given to projects with:

• a well defined UHS concept, site and subsurface basis and credible route to Front End Loading (FEL) -3 completion

• a robust cost and project delivery schedule, with validation of key costs through vendor engagement and an integrated development programme capable of supporting investment decisions

• promising commercial prospects, including a viable business model, route to market and pathway to private investment

• credible hydrogen supply and offtake arrangements

• a clear planning, consenting, environmental permitting, and safety regulation pathway

• a robust project execution strategy, supported by credible project partner and supply chain arrangements

• the potential to strengthen UK engineering, manufacturing, construction and supply chain capabilities

• a commitment to open knowledge sharing and dissemination of evidence relevant to wider UK UHS deployment

• a project development study that materially reduces the principal barriers to FID, with each funded activity linked to an identified risk, a realistic target end position, and a clear account of the risks that will remain

Your project must show a clear route to construction and operation in the UK, with a specific site identified as part of the project development study.

Your selected site may be located at a demonstration or test facility that you have an arrangement with, a facility you already own, or within a greenfield development. Your choice of proposed site will be considered in the context of the maturity and scale of your technology.

You must demonstrate a credible route to deployment, including how you will secure any outstanding permits, consents, infrastructure and site arrangements within the project timescales.

Any site preparation and development risks must be clearly outlined. Project sponsors must prioritise sites that minimise such risks.

Your project development study must contain, as a minimum:

• front end engineering design (FEED) level engineering definition

• robust cost and schedule definition

• commercial viability assessment

• hydrogen supply and offtake arrangements

• planning, consenting and regulatory progression

• project execution and procurement planning

On funding award, the detailed deliverables for each area will be agreed with UKRI through a project specific master deliverables register (MDR). This will reflect your storage technology, site-specific conditions and project maturity at the start of the funded period.

FEED level engineering definition

Your project development study must advance your project from early-stage (FEL-1 or -2) design definition towards an FEL-3 complete engineering basis. It must be supported by evidence that the proposed site, facility and associated surface and subsurface infrastructure can be delivered and operated safely.

This must include:

• a FEED level (FEL-3) basis of design with associated engineering deliverables, developed in line with the MDR agreed on funding award

• a mass balance and operating model demonstrating alignment between hydrogen supply, storage and demand requirements

• site specific subsurface characterisation demonstrating containment integrity, storage performance, and operational suitability

• a major equipment list (MEL) and technology selection report, supported by equipment sizing and datasheets

• a technical risk register documenting the identification, mitigation and residual status of key technical risks

• FEED level safety studies, including hazard identification (HAZID), environmental impact identification (ENVID), quantitative risk assessment (QRA) and design assurance activities

Robust cost and schedule definition

Your project development study must produce cost and schedule estimates sufficiently robust to support investment decisions. This includes an evidenced understanding of development expenditure (DEVEX), capital expenditure (CAPEX), operating expenditure (OPEX), key cost drivers, contingencies, critical path activities and delivery risks.

This must include:

• an Association for the Advancement of Cost Engineering (AACE) Class 3 (-20% to +30%) cost estimate and cost estimating methodology

• vendor quotations for key equipment and engineering, procurement and construction (EPC) services

• an integrated Level 3 project schedule aligned to delivery, consenting and procurement activities

• an updated funding profile showing remaining expenditure and major investment requirements through to FID and project execution

Commercial viability assessment

Your project development study must establish a credible business model and route to market. This must comprise robust project economics, an investable financing strategy, and evidence that your project has a viable pathway beyond the DEVEX funding period.

This must include:

• a detailed business case demonstrating a credible pathway to commercial operation

• a defined revenue model and value stack, including route to market strategy

• a detailed levelised cost of storage (LCOS) model with P10, P50 and P90 assessment, including forecast performance to 2030

• a defined operating model, including ownership, operational responsibilities and commercial arrangements

• an investable financing strategy, including proposed debt, equity and public funding structure

Hydrogen supply and offtake arrangements

Your project development study must establish credible hydrogen supply and offtake arrangements, supported by evidence of prospective commercial agreements, defined operating requirements, and a viable pathway to long term operation.

This must include:

• heads of terms (HoTs), memoranda of understanding (MoUs), letters of intent (LoIs) or equivalent commercial agreements with your hydrogen suppliers and offtakers

• a defined hydrogen supply and offtake strategy, including volumes, delivery arrangements, purity requirements, storage cycles and operating assumptions

• evidence of a credible pathway to long term hydrogen supply and demand arrangements beyond the demonstrator phase

• a supply and offtake risk register demonstrating material reduction of key commercial and operational risks

Planning, consenting and regulatory progression

Your project development study must materially progress planning, consenting and regulatory readiness, covering land access, environmental assessment, planning strategy, safety requirements and early engagement with relevant authorities.

This must include:

• completed pre-application engagement, including planning authority feedback and actions

• a defined consenting roadmap and programme through to key approvals

• a Control of Major Accident Hazards Regulations (COMAH) or alternative hazardous substances determination

• a regulatory engagement record, including engagement with relevant planning, environmental, safety and permitting authorities

• evidence of progression towards required land agreements

• an Environmental Impact Assessment (EIA) screening or scoping opinion

Project execution and procurement planning

Your project development study must demonstrate a credible execution strategy. This must be supported by a capable project team, clearly defined governance arrangements, supply chain engagement and plans for managing long lead equipment and key interfaces.

This must include:

• a defined project organisation and governance structure for progression to FID and EPC, with team CVs

• an integrated project delivery model and project execution plan

• a procurement strategy for key equipment and EPC services, and a vendor engagement summary

• a commissioning and operational readiness plan

• a delivery risk register identifying key execution risks and dependencies

• an insurance, bonding and guarantee strategy

Stage gates

This competition will be grant funded with additional conditions around stage gates and monitoring added to the standard Innovate UK T&Cs.

These stage gates will focus on examining your project’s key performance indicators (KPIs) and milestone ambitions. The KPI’s and milestones will be set at the beginning of the project and developed throughout and will incorporate both commercial and technical aspects.

Stage gates will allow projects the opportunity to pivot in response to steer from UKRI and in some cases external assessors, to ensure the focus on achieving outcomes by 2030 is maintained. In some instances, stage gates may result in the end of a project where UKRI feels that progress and expectations are not being effectively met.

You will be invited to suggest what would be appropriate to include in stage gate points for your project. For example, you could suggest particular sequencing for a stage gate, such as at three month intervals. You could also suggest what milestones you expect to have been met by certain points and therefore what conditions the stage gate should be based on.

This conversation will be further developed with successful applicants.

A UKRI KPI will be a first draft of your Basis of Design, which must be completed within three months of the DEVEX funded period. This is to ensure that your project is able to inform UKRI’s funding decision on whether to support the progression of successful DEVEX projects towards deployment and delivery.

Monitoring and evaluation

Evidence from the end of project review, including progress against the agreed MDR and the project's pathway to FID, may be used to inform future UKRI funding decisions. This does not confer eligibility for, or entitlement to, any future funding.

Applicants should also expect to respond to quarterly monitoring surveys as part of the R&D Missions Accelerator Programme monitoring and evaluation programme. This is in addition to standard Innovate UK monitoring requirements.

Portfolio approach

We want to fund a variety of projects comprising different technologies, markets, locations, technological maturities and themes. We call this a portfolio approach.

Research categories

We will fund feasibility studies, as defined in the guidance on categories of research and development.

Projects we will not fund

We are not funding projects that are:

• focused on laboratory scale or early stage discovery research

• limited to the development of individual materials, components, equipment or subsystems, without integration into a defined, site specific UHS project

• focused solely on technology testing or innovation, without a credible site, demonstrator proposition and pathway to FEL-3 completion

• focused primarily on hydrogen production, transportation, transmission, distribution or end use, rather than underground hydrogen storage

• focused on above ground hydrogen storage, linepack or transportable storage as the principal storage solution

• seeking funding for routine or generic project development activity that does not materially reduce the risks or uncertainties constraining progression towards FID

• primarily intended to support business as usual activity that would proceed at the same scale and pace without public funding

• focused on the production, conversion, storage or use of hydrogen derivatives or carriers including ammonia, methanol, synthetic methane or liquid organic hydrogen carriers, rather than the underground storage of gaseous hydrogen

We cannot fund projects that are:

• dependent on export performance: giving a subsidy to an organisation on the condition that it exports a certain quantity of its products to another country

• dependent on domestic inputs usage: giving a subsidy to an organisation on the condition that it uses a set percentage of UK components in their product

28 October 2026

Online briefing event: register to attend

(Briefing slides will be available to download from Supporting Information after the event)

5 November 2026

Surgery session with Innovate UK Business Connect at 11am: register to attend

13 February 2027

Applicants notified

1 May 2027

Project start by

Before you start

You must read the guidance on applying for a competition on the Innovation Funding Service before you start.

Before submitting, it is the lead applicant’s responsibility to make sure:

• that all the information provided in the application is correct

• your proposal meets the eligibility and scope criteria

• all sections of the application are marked as complete

• if collaborative, that all partners have completed all assigned sections and accepted the terms and conditions (T&Cs)

You can reopen your application once submitted, up until the competition deadline. You must resubmit the application before the competition deadline.

What we ask you

The application is split into four sections:

1. Project details.

2. Application questions.

3. Finances.

4. Project Impact.

Accessibility and Inclusion

We welcome and encourage applications from people of all backgrounds and are committed to making our application process accessible to everyone. This includes making reasonable adjustments for people who have a disability or a long-term condition and face barriers applying to us.

You can contact us at any time to ask for guidance.

We recommend you contact us at least 15 working days before this competition’s closing date to allow us to put the most suitable support in place. The support we can provide may be limited if you contact us close to the competition deadline.

You can contact Innovate UK by email or call 0300 321 4357. Our phone lines are open from 9am to 12pm and 2pm to 5pm UK time, Monday to Friday (excluding bank holidays).

This competition is open during the Christmas holiday period. However, UKRI and Innovate UK will have limited capacity to respond to queries.

We will not respond to queries received between 23 December 2026 and 4 January 2027. Responses may also be delayed after 18 December 2026.

Submit any queries well in advance of this period to allow sufficient time for a response.

1. Project details

This section provides background for your application and is not scored.

Do not include any website addresses (URLs) in your answers.

Application team

Decide which organisations will work with you on your project and invite people from those organisations to help complete the application.

Application details

Give your project’s title, start date and duration.

Research category

Select the type of research you will undertake.

Project summary

Describe your project briefly and be clear about what makes it innovative. We use this section to assign the right experts to assess your application.

Your answer can be up to 400 words long.

Public description

Describe your project in detail and in a way that you are happy to see published. Do not include any commercially sensitive information. If we award your project funding, we will publish this description. This can happen before you start your project.

Your answer can be up to 400 words long.

Scope

Describe how your project fits the scope of the competition. If your project is not in scope, it will not be sent for assessment. We will tell you the reason why.

You must briefly summarise:

• how your demonstrator fits within our definition of eligible UHS technologies

• its intended storage capacity in tonnes of hydrogen, MWh, UHS geometric volume, and number of storage silos or reservoirs

• its operating pressure range, depth, and subsurface drilling and development requirements

• its injection and withdrawal periods (days), and number of storage cycles per year

• how your project development study supports a planned UK demonstration project

• how the project targets initial deployment of 10 to 100 MWh by the end of 2030, including what is realistically achievable by 2030

• its credible pathway to commercial, GWh-scale deployment in the UK by 2035

• your current stage of design (FEL-1, FEL-2, FEL-3 or EPC)

• the relevant interfaces with hydrogen supply and offtake

• the proposed operating philosophy within the integrated system

• the selected site location

• the surface land footprint (m2) within the proposed red line boundary of the associated surface facilities

Your answer can be up to 600 words long.

2. Application questions

The assessors will score all your answers apart from questions 1 to 7. You will receive feedback for each scored question. Find out more about how our assessors assess and how we select applications for funding.

You must answer all questions.

You must not include any website addresses or links (URLs) in your answers. Any website addresses or URLs included, will not be viewed or opened.

Question 1. Applicant location (not scored)

You must state the name and full registered address of your organisation and any partners or subcontractors working on your project.

We are collecting this information to understand more about the geographical location of all applicants.

Question 2. Animal testing (not scored)

Will your project involve any trials with animals or animal testing?

You must select one option:

• Yes

• No

We will only support innovation projects conducted to the highest standards of animal welfare.

Further information for proposals involving animal testing is available at the UKRI Good Research Hub and NC3R’s animal welfare guidance.

Question 3. Permits and licences (not scored)

Will you have the correct permits and licences in place to carry out your project?

We are unable to fund projects which do not have the correct permits or licences in place by your project start date.

You must select one option:

• Yes

• No

• In the process of being applied for

• Not applicable

Question 4. International collaboration (not scored)

Does your proposed work involve any international collaboration or engagement?

You must provide details of any expected international collaboration or engagement. You must include a list of the names and the countries, any international project co-leads, project partners, visiting researchers, or other collaborators are based in. You must also include details of any subcontractors or service providers.

If your proposed work does not involve international collaboration or engagement, your answer must confirm this.

Question 5. Export licence (not scored)

You must indicate whether an export control license is required for this project under the academic export control guidance.

You must select one option:

• Yes

• No

Question 6. Trusted Research and Innovation (not scored)

You must explain if your proposed project work relates to UKRI’s Trusted Research and Innovation (TR&I) Principles, including:

• a list of any dual use (both military and non-military) applications to your research

• a list of the areas where your project is relevant to one or more of the 17 areas of the UK National Security and Investment (NSI) Act

• whether an export control license is required for this project under the academic export control guidance and the status of any applications

• a list of any items or substances on the UK Strategic Export Control List

If your proposed work does not relate to UKRI’s TR&I Principles, your answer must confirm this.

We may ask you to provide additional TR&I information at a later date, in line with UKRI TR&I Principles and funding terms and conditions.

Question 7. Technology (unscored)

Which Underground Hydrogen Storage (UHS) technology is proposed for your project?

You must select one:

• engineered lined shaft

• subsurface silo or vertical pipe array

• engineered lined rock cavern

• depleted oil field

• depleted gas field

• novel salt cavern

• other (please specify)

This question is intended to determine whether the proposed project falls within an eligible UHS technology category.

The technology type will not determine the strategic value of a project or its suitability for support. Assessment will therefore focus primarily on the proposed demonstrator outcome, the knowledge gaps addressed, the value of evidence generated, and the credibility of the pathway towards commercial scale deployment. These aspects are considered under Question 8 and subsequent scored questions.

Your answer can be up to 100 words long.

Question 8. Development Expenditure (DEVEX) outcomes and pathway to demonstration.

Describe your definition of a ‘demonstrator’ that could be realistically delivered by 2030 and outline how the proposed DEVEX study will advance the project towards Final Investment Decision (FID).

A detailed demonstrator design is not expected at this stage.

Describe the demonstrator at a level that shows what it would prove and why. Focus your answer on how the DEVEX study will move the project towards it.

Explain:

• why the proposed scale and configuration represent a credible demonstrator required to validate the technology, site or integrated storage system under representative operating conditions

• the earliest realistic dates your project could reach Final Investment Decision (FID) and initial deployment

• the critical dependencies that determine them, and the development, consenting, financing and procurement activities required after the funded DEVEX period to achieve them

• the key deliverables and evidence required by Front End Loading (FEL) -3 completion to support an investment decision for the demonstrator

• up to five measurable key success criteria for the demonstrator, including the associated performance metrics and research questions or work packages needed to demonstrate success

• how successful demonstration would support commercial pull through for the project and wider UHS sector

• the transferability of learning, repeatability, cost reduction and pathway to commercial, gigawatt hour (GWh) scale UHS deployment in the UK by 2035

Your answer can be up to 600 words long.

You must submit a single appendix containing a proposed Master Deliverables Register (MDR) for FEL-3 completion of the demonstrator, using the MDR template provided,, to support your answer. The MDR must identify the project-specific technical, commercial, planning, consenting and delivery outputs required to achieve FEL-3 completion and support progression towards FID.

You can submit one appendix to support your answer. It can include diagrams and charts. It must be a PDF no larger than 10MB. It can be up to two A4 pages and must be legible at 100% zoom.

Question 9. Current project maturity

Describe your proposed UHS project and its current stage of development.

Explain:

• the proposed UHS concept, including the storage type, geology or host formation, principal surface and subsurface components, and overall configuration

• the project’s current engineering design stage (FEL-1 or FEL-2), including the basis for the stated maturity

• the principal design decisions and assumptions established to date, and a credible plan for progression to FEL-3 completion

• the site specific evidence currently available, including relevant seismic, well, core, geological or ground investigation data, and any assessment of containment integrity and storage performance

• the technical studies, engineering activities, testing, trials or previous deployment completed to date, including the principal deliverables and evidence generated

• the project’s current land access and site control position, including the land and subsurface rights required

• engagement with relevant landowners and rights holders, and the status of any options, leases, licences or other agreements

• your current safety and regulatory position, including hazard assessments completed, engagement with the Health and Safety Executive (HSE) and environmental regulator,

• your current view on Control of Major Accident Hazards Regulations (COMAH) and Hazardous Substances Consent

Your answer can be up to 600 words long.

Question 10. Cost and schedule

Describe the current cost and schedule maturity of your proposed UHS demonstrator project and how these will be developed during the funded period to support progression towards FID.

Explain:

• your total development expenditure incurred to date, with a summary of the activities and outputs it has funded

• your current cost estimate for DEVEX, Capital Expenditure (CAPEX) and Operating Expenditure (OPEX) associated with delivery and operation of the project

• the basis, scope, class and accuracy range of your current DEVEX, CAPEX and OPEX estimates, including the estimating methodology, key assumptions, exclusions, contingencies and available evidence supporting the stated cost maturity

• the principal cost drivers and uncertainties, including those associated with subsurface investigations, wells, surface facilities, compression and processing, connections, consenting and project delivery

• your current project programme, including its schedule maturity, principal phases, stage gates, critical path, long lead items, dependencies and target dates for FEL-3 completion, FID and initial operation

• how the funded DEVEX study will improve the cost estimate and schedule, including the proposed pathway to an AACE Class 3 estimate and integrated Level 3 project schedule by the end of the funded period

• the principal cost and schedule risks that could prevent or delay progression towards FID, together with the proposed mitigation measures and the evidence that will demonstrate material risk reduction

Your answer can be up to 600 words long.

You can submit two appendices to support your answer. It can include diagrams and charts. It must be a PDF no larger than 10MB. It can be up to two A4 pages and must be legible at 100% zoom. It must include a line item DEVEX and CAPEX cost breakdown covering key equipment items or summarised costs for subsurface development, above ground facility, hydrogen supply and offtake integration, facility balance of plant, and project development and services. Please state the cost estimate class, basis of estimate, contingency and commentary of available supporting evidence, using the Cost Estimate RFI template provided.

You must provide costs in 2026 British Pound Sterling (GBP) for the projected cost of the integrated demonstrator project, stating relevant key assumptions, exclusions, and the cost boundary used. This must include whether hydrogen supply is assumed to be available on site or delivered from an external interface, and whether storage system costs are measured from the hydrogen receipt flange through to the delivery flange for the intended offtakers.

You must also submit a project plan or Gantt chart as an appendix to support your answer. It must be a PDF no larger than 10MB. It can be up to two A4 pages and must be legible at 100% zoom.

Question 11. Commercialisation potential

Describe the commercialisation potential of your proposed demonstrator project and how it could progress towards an investable, market-led project and subsequent commercial-scale deployment in the UK?

Explain:

• the priority offtake use case(s), target customers and energy system needs, and any evidence supporting the estimated UK and international market opportunity

• the proposed commercial and operating model, including the customer proposition, route to market, asset ownership, responsibilities for development and operation, anticipated revenue streams, and any expected requirement for public or revenue support

• your preliminary project economics, including the principal commercial assumptions, target Levelised Cost of Storage (LCOS), and expected competitiveness against relevant UHS technologies and alternative storage or flexibility solutions

• the regulatory, standards, certification, insurance and other requirements affecting wider UK deployment and commercialisation

• the commercial evidence the project development study will generate to support decisions by customers, investors, insurers, financiers and relevant energy system bodies, and demonstrate a viable pathway beyond the DEVEX funding period

• the staged investment required to progress through demonstration, first commercial deployment and subsequent scale-up, including the intended sources of finance and status of engagement with prospective investors and financiers.

Your answer can be up to 600 words long.

Question 12. Barriers to progress and risk reduction

Describe the principal barriers and risks currently preventing your UHS project from progressing towards FID, and how the funded project development study will address them

Explain:

• the principal barriers and risks across technical and subsurface development, cost and schedule, hydrogen supply and offtake, land access, planning and consenting, environmental permitting, safety and regulation, commercial viability, financing and project delivery

• which barriers and risks are within your control and which depend on counterparties, regulators, markets or policy, including hydrogen production and demand, supplier and offtaker investment decisions, planning and permitting decisions, regulatory positions and future revenue support

• the specific activities and deliverables within the funded project development study that will address each principal barrier or risk,

• how these activities and deliverables will advance hydrogen supply and offtake arrangements and the project’s planning, consenting and regulatory position

• the prospective hydrogen suppliers and offtakers identified, their intended roles, the status of engagement and any Letters of Intent, Memoranda of Understanding, Heads of Terms or equivalent commercial agreements in place or under development

• the principal planning, consenting and permitting risks that could delay or prevent progression towards FID, including the approvals required, key dependencies and potential effects on project cost and schedule

• the expected position at the end of the funded period, clearly identifying which barriers and risks will be resolved, materially reduced, or remain outstanding, with an indication as to how you intend to address them after the funded period

Your answer can be up to 600 words long.

Question 13. Team and resources

Describe your project team and their roles, organisation and responsibilities.

Explain:

• the roles and responsibilities of each project partner organisation, including who will lead the project, own key decisions and deliver the principal work packages and project development study outputs

• the roles and relevant expertise of the core project team, including technical, subsurface, commercial, planning, consenting, safety, cost, schedule and project-delivery expertise

• the external organisations required to deliver the project, including engineering consultants, specialist advisers, subcontractors, suppliers and prospective delivery partners, and the status of their engagement

• the existing relationships and contractual arrangements between partners, how the consortium will work together and how responsibilities will evolve during and after the funded period

• any capability or resource gaps, including roles still to be recruited or procured, the proposed approach and timescale for filling them, and how associated delivery risks will be mitigated

Your answer can be up to 600 words long.

You can submit an appendix containing letters of support. The appendix must be a PDF no larger than 10MB and must be legible when viewed at 100% zoom.

You can include multiple letters of support in a single appendix. Each letter should be no more than one A4 page and should confirm the commitment or support of the organisation providing it.

Letters of support must not introduce substantive new information not included elsewhere in your application. Assessors will not use letters of support as part of their assessment, other than to confirm support or commitment from any organisations referenced.

Question 14. Project management

Describe how you will govern, manage and control the funded project to ensure its successful delivery.

Explain:

• the main work packages of your project, indicating the lead partner and total cost of each and covering key milestones, dependencies, critical path, outputs and dissemination activities

• your approach to project management, identifying any major tools and mechanisms you will use to get a successful and innovative project outcome aligned with your theory of change

• your approach to technical assurance, document control and approval of key outputs, including management of the Master Deliverables Register and evidence required to demonstrate progression towards FEL-3

• any output likely to be subject to regulatory requirements, certification, ethical issues and other requirements identified, and how you will manage this

Your answer can be up to 600 words long.

You must submit a single appendix containing a project governance and responsibility matrix or organisation chart to support your answer. It must identify the governance bodies, principal work packages, accountable owners, approval authorities and reporting or escalation routes. You must submit a project plan or Gantt chart as an appendix to support your answer. It must be a PDF no larger than 10MB. It can be up to two A4 pages and must be legible at 100% zoom.

Question 15. UK economic and supply chain benefits

Describe how your project will generate economic benefits and strengthen UK engineering, manufacturing, construction, skills and supply-chain capabilities through DEVEX, demonstrator delivery and subsequent commercial deployment.

Explain:

• the UK organisations and supply-chain capabilities required to develop, construct, commission, operate and maintain the proposed demonstrator, including any critical dependencies on overseas suppliers

• how you will identify, engage and provide accessible opportunities for UK suppliers, including SMEs, start-ups, academic institutions and voluntary, community and social enterprises

• the principal gaps or constraints in current UK engineering, manufacturing, construction and supply-chain capability, and how your project will help address them

• how the capabilities, intellectual property, knowledge and supplier relationships developed through the project could support replication, export opportunities and commercial, GWh-scale UHS deployment in the UK by 2035

Your answer can be up to 400 words long.

3. Finances

Each organisation in your project must complete their own project costs, organisation details and funding details in the application. Academic institutions must use the Transparent Approach to Costing (TRAC) method and upload to IFS to support their costs. This is a replacement to the Je-S form which has now been decommissioned.

For an overview on what costs you can claim, see our project costs guidance. Note this is general guidance, for specific guidance see the eligibility section in this competition. You can also view our application finances video.

4. Project Impact

This section is not scored but will provide background to your project.

Each partner must complete the Project Impact questions before being able to submit the application.

More information can be found in our Project Impact guidance and by viewing our Impact Management Framework video.

Innovate UK complies with the requirements of UK GDPR and the Data Protection Act 2018, and is committed to upholding data protection legislation, and protecting your information in accordance with data protection principles.

Assessment

Your application will be reviewed by five independent assessors based on the content of your application and their skills or expertise relevant to your project. All of the scores awarded will count towards the total score used to make the funding decision unless you are notified otherwise.

You can find out more about our assessment process in the General Guidance.

Your submitted application will be assessed against these criteria:

Underground hydrogen storage demonstrator DEVEX support assessor guidance for applicants.pdf

Background and further information

The Clean Energy Superpower Mission (CESM) is part of the UKRI R&D Missions Accelerator Programme (RDMAP). This flagship new mission led approach is backed through to 2030 by at least £500 million of funding provided by Department for Business, Innovation, Science and Trade (previously coming under Department of Science, Innovation and Technology).

UKRI’s CESM has launched two research and innovation (R&I) challenges covering:

• consumer led flexibility (CLF)

• ultra long duration energy storage (ULDES)

The second challenge aims to accelerate the UK’s commercialisation, manufacture and deployment of ULDES technologies. These will focus on technologies and systems which can affordably meet demands of over 100 hours continuously. It aims to build UK manufacturing capacity, supply chains, skilled jobs, and investor confidence, and associated export opportunities.

Underground hydrogen storage (UHS) has been chosen as a priority ULDES technology due to its potential to provide large scale, multi-day to interseasonal energy storage capacity required to support a future low carbon energy system. By storing significant volumes of hydrogen over extended periods, UHS could play a critical role in addressing prolonged supply demand imbalances and improve system resilience and energy security.

The UK has several potential competitive advantages in UHS, including favourable geological resources, internationally recognised subsurface expertise, established engineering and energy sector capabilities, and a growing pipeline of prospective projects. Successful deployment could strengthen UK capability across engineering, construction, subsurface services and associated supply chains. Targeted support for large scale demonstrator development could help accelerate commercialisation and retain these economic and strategic benefits within the UK.

However, UHS technologies remain at an early stage of commercial development in the UK. While hydrogen salt cavern projects are progressing towards deployment, alternative UHS technologies have limited operational precedent. These include subsurface silos, engineered lined shafts, lined rock caverns and porous rock storage, and face a range of technical, commercial, regulatory and delivery challenges. Significant uncertainty remains around project costs, business models, consenting pathways, hydrogen supply and offtake arrangements, and the evidence required to support investor confidence and future deployment.

The UHS DEVEX programme therefore seeks to establish a pipeline of investable demonstrator projects capable of generating the evidence required to support wider commercial deployment of UHS in the UK. Demonstrator projects are expected to provide critical learning on technical performance, operability, deliverability, commercial viability and system value, while helping to reduce uncertainty for future projects and investment.

Hydrogen storage has a critical role alongside low carbon dispatchable power (LCDP) and is one of the few clean storage solutions capable of providing 100 hours or more of reserve power at the scale required. . The 7th Carbon Budget includes just under 40 GW of LCDP in 2050, and hydrogen to power is expected to have a strong economic advantage over gas CCUS at low load factors.

The UK has distinct geological advantages for hydrogen storage. These include, but are not limited to, salt caverns, which are not always located near renewable generation.

Targeted R&I now is an essential part of de-risking carbon budgets.

The RDMAP ULDES Challenge is also supporting the development of electrochemical ULDES demonstration projects in the UK. A Ultra Long Duration Energy Storage Project Development Studies competition was closed earlier this year. The aim of this was to support the development, scale-up, and UK manufacture of electrochemical ULDES technologies. Phase 2 of the electrochemical stream is expected to launch in the middle of 2027.

Find out more about the wider ULDES programme: New challenge launched to store clean energy for longer (opens in new window).

Available support

We will be working with Innovate UK Business Connect (IUKBC), who will deliver and manage an [online matchmaking tool](https://www.b2match.com/e/rdmap-energy-underground-hydrogen/components/77173%20() to be open throughout the duration of the competition. IUKBC will also host a series of ‘surgery sessions’ for potential applicants to sign up to. These will offer applicants the opportunity to network with others and ask further questions on the competition.

Research, Development and Innovation Streamlined Scheme Information

This award is being offered under the Research, Development and Innovation Streamlined Subsidy Scheme in accordance with section 10(4) of the Subsidy Control Act 2022.

Projects funded must meet the following definition(s):

Category 1: Feasibility study

The evaluation and analysis of the potential of a project, which aims at supporting the process of decision-making. This is done by objectively and rationally uncovering its strengths and weaknesses, opportunities and threats, as well as identifying the resources required to carry it through and ultimately its prospects for success.​

Briefing recording and slides

Briefing recording and slides will be available to download here after the briefing event.

What happens if you receive a grant offer

If you have passed your initial assessment and have received an email with a grant offer, you will be asked to complete the project setup process on the Innovation Funding Service (IFS). Watch our video on what steps are there before a project starts.

We will ask for information that will allow us to undertake mandatory checks on your organisation and the eligibility of your costs, as well as review the documentation for your project.

You must follow the unique link embedded in your email notification. This takes you to your project's dedicated IFS Set Up portal, where we gather the information required to set up your project, for example, your bank details. Watch our video on how successful applicants receive their funding.

If your application is unsuccessful

If you are unsuccessful with your application this time, you can view feedback from the assessors. This will be available to you on your IFS portal following notification.

Sometimes your application will have scored well, and you will receive positive comments from the assessors. You may be unsuccessful as your average score was not above the funding threshold or your project has not been selected under the portfolio approach if this is applied for this competition.

Find a project partner

If you want help to find a project partner, contact Innovate UK Business Connect.

Support for SMEs from Innovate UK Business Growth service

Innovate UK Business Growth helps innovation focused businesses make the best strategic choices and access the right resources, in order to grow and ultimately achieve scale.

Visit the service’s website to learn about how you might benefit as a winner.

Protecting your innovation

A Secure Innovation campaign has been developed to help founders and leaders of innovative startups protect their technology, competitive advantage, and reputation.

This was developed by UK’s National Protective Security Authority (NPSA) and the National Cyber Security Centre (NCSC).

Data sharing

This competition is operated by Innovate UK and UK Research and Innovation (UKRI).

Innovate UK and UKRI are directly accountable to you for its holding and processing of your information, including any personal data and confidential information. Data is held in accordance with our own policies.

Innovate UK may also share any relevant information submitted and produced during the application process concerning your application with Innovate UK’s national and regional UK third parties and partners who may contact you. For more information see how we handle grant applicant and grant holder data.

Innovate UK, UKRI and Innovate UK Business Connect will be data controllers for personal data submitted during the application.

Innovate UK’s Privacy Policy

Innovate UK Business Connect Privacy Policy

UKRI Privacy Policy

Innovate UK and UKRI comply with the requirements of UK GDPR and the Data Protection Act 2018, and is committed to upholding data protection legislation, and protecting your information in accordance with data protection principles.

The Information Commissioner’s Office also has a useful guide for organisations, which outlines the data protection principles.

Contact us

If you need more information about how to apply or you want to submit your application in Welsh, email support@iuk.ukri.org or call 0300 321 4357.

Our phone lines are open from 9am to 12pm and 2pm to 5pm UK time, Monday to Friday (excluding bank holidays).

This competition is open during the Christmas holiday period. However, UKRI and Innovate UK will have limited capacity to respond to queries.

We will not respond to queries received between 23 December 2026 and 4 January 2027. Responses may also be delayed after 18 December 2026.

Submit any queries well in advance of this period to allow sufficient time for a response.

Innovate UK or any of our partners will not tolerate abusive language in any written or verbal correspondence, applications, social media or any other form that might affect staff.