Pre-commercial appraisal for CO2 aquifer storage

The upcoming Horizon Europe grant opportunity identified as HORIZON-CL5 focuses on the pre-commercial appraisal for CO2 aquifer storage. The call is scheduled to open on December 18, 2025, with a submission deadline of March 31, 2026. A total budget of €25 million is allocated for this initiative, which aims to support five projects at €5 million each. This funding opportunity specifically addresses the need for geological storage of carbon dioxide, especially in Central, Eastern, and Southern Europe, which are identified as priority regions. The objective is to accelerate the development of CO2 storage sites by providing financial resources for projects that identify and appraise suitable geological formations and conduct pilot injection tests in deep saline aquifers, which must be at least 800 meters deep. Eligible applicants include research institutions, universities, commercial enterprises (both SMEs and large companies), and public-private partnerships capable of performing technological developments and pre-commercial validations. Cooperation with national competent authorities is emphasized, as their involvement is critical for selecting appropriate sites and ensuring regulatory compliance. The funding will be provided as a lump sum grant, allowing beneficiaries greater flexibility in managing resources without the burden of detailed cost tracking. The application process will consist of a single-stage submission, requiring complete project proposals without an initial expression of interest phase. Activities funded by this initiative will encompass geological mapping, data acquisition, drilling, monitoring technologies, and pilot testing to evaluate the injectivity of proposed storage sites. The focus on deep saline aquifer storage aims to close existing storage capacity gaps in the targeted regions, contributing to the overarching goals of the EU’s Carbon Capture, Utilization, and Storage strategy. Overall, this grant opportunity represents a significant effort to enhance CO2 storage capabilities within Europe and seeks innovative partnerships to pave the way for sustainable energy practices while addressing climate change mitigation.

This is a Horizon Europe call under the BATTERIES and ENERGY theme, specifically targeting pre-commercial appraisal for CO2 aquifer storage. The call, identified as HORIZON-CL5, is for HORIZON Innovation Actions (HORIZON-IA) and offers a HORIZON Lump Sum Grant. The planned opening date is December 18, 2025, and the deadline for submissions is March 31, 2026, at 17:00 Brussels time.

The expected outcome of projects funded under this topic is to support pre-commercial CO2 geological storage appraisal, speed up storage site development, support planning of CO2 capture projects (and related source to store linkages), and help close the storage capacity gap, particularly in Central, Eastern, and Southern Europe.

The scope of the projects should include carrying out a storage site identification and appraisal program with at least one injection pilot test in a deep saline aquifer. Injection tests can use water only to reduce costs and duration, but may also include water with CO2 or N2 to determine reservoir injectivity with different phases. Cooperation with a national competent authority is expected to ensure support in selecting priority target formations and accessing existing subsurface data. Projects must demonstrate how the test site was identified and that CO2 storage is legally possible in the designated area.

Test sites must be in a saline aquifer at a minimum depth of 800 meters, in a geologically stable area with minimal faulting and fracturing, providing significant scalable storage capacity with proven confinement, limited heterogeneity, and favorable porosity and permeability. The sites are expected to gain the necessary permits following appraisal and testing. The geological conditions of the site should be defined in terms of risks, demonstrating that prior analysis shows no significant risk of leakage or damage to human health or the environment under the proposed conditions of use.

Tests should be designed to allow reliable quantification of the injectivity index, with optimized duration to achieve a representative pressure transient response. The Horizon Europe grant can support all data acquisition, processing, and interpretation, modeling, drilling, completion and logging of the test well, the injectivity test, and measuring & monitoring technologies. These operations can be carried out by the consortium or subcontracted. This topic contributes to the R&I activity in the SET-Plan CCUS Implementation Plan to unlock CO2 storage capacity through support to pre-commercial appraisal activities.

General conditions for participation include:

1. Admissibility Conditions:Proposal page limit and layout as described in Annex A and Annex E of the Horizon Europe Work Programme General Annexes and Part B of the Application Form available in the Submission System.

2. Eligible Countries as described in Annex B of the Work Programme General Annexes. Specific provisions exist for non-EU/non-Associated Countries, detailed in the Horizon Europe Programme Guide.

3. Other Eligible Conditions:Projects using satellite-based earth observation, positioning, navigation, and/or related timing data and services must use Copernicus and/or Galileo/EGNOS. Compliance with Annex B of the Work Programme General Annexes is required.

4. Financial and operational capacity and exclusion criteria are described in Annex C of the Work Programme General Annexes.

5. Evaluation and award:Award criteria, scoring, and thresholds are described in Annex D of the Work Programme General Annexes. Submission and evaluation processes are detailed in Annex F of the Work Programme General Annexes and the Online Manual. The indicative timeline for evaluation and grant agreement is described in Annex F of the Work Programme General Annexes.

6. Legal and financial set-up of the grants:Eligible costs will take the form of a lump sum as defined in the Decision of 7 July 2021. Further details are in Annex G of the Work Programme General Annexes.

Specific conditions are described in the specific topic of the Work Programme.

Application and evaluation forms and model grant agreement (MGA):

Application form templates are available in the Submission System, including the Standard application form (HE RIA, IA). Evaluation form templates will be used with necessary adaptations, including the Standard evaluation form (HE RIA, IA).

Guidance documents include the HE Programme Guide, Lump Sum MGA, Detailed budget table (HE LS), and Guidance: "Lump sums - what do I need to know?".

Additional documents include:HE Main Work Programme 2026-2027 – 1. General Introduction, HE Main Work Programme 2026-2027 – 8. Climate, Energy and Mobility, HE Main Work Programme 2026-2027 – 15. General Annexes, HE Programme Guide, HE Framework Programme 2021/695, HE Specific Programme Decision 2021/764, EU Financial Regulation 2024/2509, Decision authorising the use of lump sum contributions under the Horizon Europe Programme, Rules for Legal Entity Validation, LEAR Appointment and Financial Capacity Assessment, EU Grants AGA — Annotated Model Grant Agreement, Funding & Tenders Portal Online Manual, Funding & Tenders Portal Terms and Conditions, and Funding & Tenders Portal Privacy Statement.

The budget overview for the year 2026 includes several topics:

HORIZON-CL5-2026-03-D2-02 - HORIZON-RIA:€14,200,000, indicative number of grants: 3, contributions around €4,700,000.

HORIZON-CL5-2026-03-D3-01 - HORIZON-RIA:€9,000,000, indicative number of grants: 3, contributions around €3,000,000.

HORIZON-CL5-2026-03-D3-12 - HORIZON-RIA:€15,000,000, indicative number of grants: 3, contributions around €5,000,000.

HORIZON-CL5-2026-03-D3-13 - HORIZON-IA:€31,500,000, indicative number of grants: 3, contributions around €10,500,000.

HORIZON-CL5-2026-03-D3-18 - HORIZON-IA:€20,000,000, indicative number of grants: 2, contributions around €10,000,000.

HORIZON-CL5-2026-03-D3-19 - HORIZON-IA:€24,000,000, indicative number of grants: 3, contributions between 4,000,000 and €12,000,000.

HORIZON-CL5-2026-03-D3-20 - HORIZON-IA:€14,000,000, indicative number of grants: 2, contributions around €7,000,000.

HORIZON-CL5-2026-03-D3-21 - HORIZON-RIA:€12,000,000, indicative number of grants: 3, contributions around €4,000,000.

HORIZON-CL5-2026-03-D3-22 - HORIZON-IA:€12,000,000, indicative number of grants: 2, contributions around €6,000,000.

HORIZON-CL5 - HORIZON-IA:€25,000,000, indicative number of grants: 5, contributions around €5,000,000.

Partner search announcements are available for collaboration on this topic. The submission system is planned to open on the date stated on the topic header.

For support, applicants are encouraged to read all provisions carefully, consult the Online Manual and Horizon Europe Programme Guide, check the Funding & Tenders Portal FAQ, and contact the Research Enquiry Service, National Contact Points (NCPs), Enterprise Europe Network, IT Helpdesk, European IPR Helpdesk, and CEN-CENELEC/ETSI Research Helpdesks. Partner Search tools are also available.

In summary, this Horizon Europe call aims to foster innovation in CO2 capture and storage by supporting projects that appraise geological storage sites, particularly in regions where storage capacity is lacking. It encourages collaboration with national authorities and the use of advanced technologies for site characterization and monitoring, with the ultimate goal of accelerating the deployment of CCUS technologies and contributing to climate change mitigation efforts. The funding is provided as a lump sum, and applicants should carefully review all guidelines and conditions to ensure their proposals are eligible and competitive.

Eligible Applicant Types:The eligible applicant types are not explicitly stated in the provided text. However, given that it is a Horizon Europe call, eligible applicants typically include universities, research institutes, SMEs, large enterprises, and other organizations involved in research and innovation activities. The specific eligibility criteria are detailed in Annex B of the Work Programme General Annexes and the Horizon Europe Programme Guide.

Funding Type:The primary financial mechanism is a grant, specifically a HORIZON Lump Sum Grant, as indicated by the Type of MGA (Model Grant Agreement) being "HORIZON Lump Sum Grant [HORIZON-AG-LS]". The eligible costs will take the form of a lump sum as defined in the Decision of 7 July 2021.

Consortium Requirement:The text does not explicitly state whether a single applicant or a consortium is required. However, given the scope of the projects, which involve appraisal programs and pilot tests, it is highly likely that a consortium of multiple applicants is preferred or even required to bring together the necessary expertise and resources.

Beneficiary Scope (Geographic Eligibility):The geographic eligibility is primarily focused on EU and associated countries, as indicated by the reference to Annex B of the Work Programme General Annexes and the Horizon Europe Programme Guide. However, the text also mentions that a number of non-EU/non-Associated Countries have made specific provisions for funding their participants in Horizon Europe projects.

Target Sector:The program targets the energy and climate sectors, specifically focusing on Carbon Capture, Utilization, and Storage (CCUS) technologies. The specific topic, HORIZON-CL5, aims to support pre-commercial CO2 geological storage appraisal.

Mentioned Countries:The text does not explicitly mention specific countries. However, it refers to Central, Eastern, and Southern Europe as regions where support for closing the storage capacity gap is particularly needed. It also mentions EU and associated countries, as well as non-EU/non-Associated Countries that have made provisions for funding their participants.

Project Stage:The expected maturity of the project is pre-commercial appraisal. The projects should focus on storage site identification and appraisal, including injection pilot tests in deep saline aquifers. The aim is to speed up storage site development and support the planning of CO2 capture projects.

Funding Amount:The budget for the topic HORIZON-CL5 is €25,000,000. The indicative number of grants is 5, suggesting an average funding of around €5,000,000 per project. Other topics listed have varying budgets and indicative grant amounts. For example, HORIZON-CL5-2026-03-D3-19 has a budget of €24,000,000 with an indicative grant range of €4,000,000 to €12,000,000.

Application Type:The application type is an open call, as indicated by the single-stage submission process and the forthcoming deadline model.

Nature of Support:Beneficiaries will receive money in the form of a lump sum grant to cover eligible costs, as defined in the Decision of 7 July 2021. The grant can support data acquisition, processing, interpretation, modelling, drilling, completion and logging of test wells, injectivity tests, and measuring & monitoring technologies.

Application Stages:The application process is single-stage, meaning applicants submit a full proposal by the deadline.

Success Rates:The success rates are not explicitly mentioned.

Co-funding Requirement:The text does not explicitly state whether co-funding is required.

Summary:This Horizon Europe call, specifically topic HORIZON-CL5, focuses on "Pre-commercial appraisal for CO2 aquifer storage." It aims to support projects that identify and appraise geological storage sites for CO2, particularly in deep saline aquifers, to unlock CO2 storage capacity and support the development of Carbon Capture, Utilization, and Storage (CCUS) technologies. The call is open to a wide range of applicants from EU and associated countries, as well as some non-EU countries, and encourages cooperation with national competent authorities. The funding is provided as a lump sum grant, with a total budget of €25,000,000 for the topic and an indicative grant size of around €5,000,000 per project. The application process is single-stage, with a deadline of March 31, 2026. The projects should contribute to the SET-Plan CCUS Implementation Plan and help close the storage capacity gap, especially in Central, Eastern, and Southern Europe. The grant supports various activities, including data acquisition, pilot tests, and the development of measuring and monitoring technologies.