CRU Decision on Long Duration Energy Storage Procurement

The Decision implements Action 6 of the Department of Climate, Energy and the Environment's Electricity Storage Policy Framework, published in July 2024.

EirGrid published its consultation on the LDES procurement mechanism on 13 October 2025. EirGrid then submitted its recommendation paper to the CRU on 1 July 2026, having revised several proposals in light of stakeholder feedback.

The Decision

The Decision broadly endorses EirGrid’s framework, a technology-neutral procurement, a two-stage qualification and tender process, operation under a Trading Envelope and a competitively bid revenue floor. The key features of the Decision are set out below.

Volume

The CRU agreed to increase the procurement volume from the previously indicated range of 201–300 MW to a maximum of 500 MW. The 500 MW is a ceiling rather than a target. The final volume will depend on the outcome of the competition, and EirGrid must notify the CRU of the projects it proposes to contract, aggregate volume and expected cost to consumers before contracts are awarded. The approval relates only to this initial round.

Eligibility

The eligibility criteria consulted on have been largely retained, including a minimum round-trip efficiency of 75%, meaning an asset must be able to return at least 75% of the electricity it takes in.

A notable change in response to stakeholder feedback is that projects need only hold a Connection Offer at qualification stage, with a Connection Agreement required at tender stage. Final planning consents and evidence of land rights are also required. Co-located hybrid sites must have at least 30 MW of transmission-connected renewable generation.

Trading Envelope

The Trading Envelope (called the “Operational Envelope” in EirGrid’s consultation) is the operating framework for contracted LDES assets. Each day, EirGrid will issue each asset with time-specific limits on how much it may import and export over the following trading day.

The Trading Envelope will directly affect how much an asset can earn in the market and therefore how much revenue floor support it will need. The CRU has accepted that bidders cannot accurately price their bids unless they know how EirGrid will set these limits.

EirGrid must therefore develop and publish a Trading Envelope methodology before the tender. The methodology and issuance timing will sit in a separate “Protocol Document” rather than in individual contracts, and any material change will require public consultation and CRU approval.

Revenue Floor and Sharing

The revenue floor is the core financial support under the scheme. Each bidder will submit the minimum annual revenue it needs, and successful bidders receive the figure they bid (“pay-as-bid”). To protect consumers, bids cannot exceed a cap informed by an independent Levelised Cost of Storage (“LCOS”) assessment. Performance against the floor is assessed annually. Where revenues exceed the floor, the asset keeps 70% of the upside and 30% is returned to consumers through transmission charges.

A key point for bidders is how revenues are measured. Many respondents argued for a net-of-costs basis, but the CRU confirmed a “gross” basis. Only the cost of buying electricity to charge the asset, including efficiency losses, is deducted before revenues are compared with the floor. The LCOS methodology, which will determine the cap, has not yet been shared with developers.

Contract Length & Market Access

The CRU has approved a ten-year service duration. EirGrid proposed this term to reflect the immediate procurement requirement and the anticipated evolution of market arrangements, such as EU market integration following the Celtic Interconnector. A large majority of respondents considered this too short, given LDES asset lifetimes of 25–50 years or more.

The CRU stressed that this is an initial procurement round rather than an enduring framework, and that a shorter term helps to manage consumer exposure while allowing lessons to inform future rounds. Contracted assets will keep full access to all Single Electricity Market markets, subject only to complying with their Trading Envelope.

Tender Assessment

Bidding will take place in two stages. First, applicants must pass a pass/fail qualification stage based on (i) company criteria, such as financial turnover and relevant experience, and (ii) project criteria, such as a valid Connection Offer and technology maturity. Qualified bidders who then meet further pass/fail requirements at tender stage, including a Connection Agreement, planning consents, land rights and a revenue floor bid within the cap, will be scored against three weighted criteria:

• Cost (50%): rewards lower revenue floor bids.
• Impact (30%): measures a project's potential to reduce renewable dispatch-down and to remain available to the system.
• Connection Method (20%): hybrid projects with at least 30 MW of renewable generation, or projects with an existing standalone connection, receive full marks, while projects needing a new standalone transmission connection score zero.

The CRU has also approved in principle a new Best and Final Offer stage, which did not feature in the original consultation. The highest-ranked bidders will be shortlisted, with a buffer above the procurement volume to allow for projects that fall away. At this stage, EirGrid will review each shortlisted project’s connection programme and set a target energisation date, its best estimate of when the project can connect. This deliverability test is pass/fail. A project will not proceed if its target energisation date is later than four months before the scheme commencement date, which allows time for Grid Code testing.

Next Steps and Conclusion

The Decision provides clarity on the overall framework for Ireland's first LDES procurement. However, several elements that will directly affect bankability have yet to be finalised, and EirGrid will now consult on them as part of the contractual arrangements. These include: (i) the trading non-activity scalar; (ii) non-compliance charges for assets that trade outside their Trading Envelope; (iii) the Trading Envelope methodology; (iv) the deliverability assessment and target energisation date methodology; (v) governance and change-control arrangements; and (vi) whether to publish, and engage stakeholders on, the LCOS methodology.

These details will determine how much a project can earn and how much support it needs, so bidders will not be able to price with certainty until they are published. Following the consultation, EirGrid will submit a further recommendation paper and the CRU will issue a further decision before tenders are invited. The Decision does not set dates for the qualification or tender stages but instead the CRU notes EirGrid’s commitment to provide more detail on procurement timelines through the contractual arrangements consultation. EirGrid’s October 2025 consultation suggested a timeline with the procurement round launching in Q1 2027 and contracts being executed in Q4 2027.