At present, Europe has an industrial leadership on electrolyser technologies with about two thirds of main players globally. The industrial competitiveness and the quality of the technologies together with the background competences should be supported by a continuous development process looking to both incremental improvements and breakthrough innovations, trying to keep competitiveness in both available solutions in the market and next generation technologies. Alkaline electrolysers are, in this respect, a mature and consolidated technology, available in the market at large scale, looking to play the challenge of lighthouse project initiatives at the scale of hundreds of megawatts (MW) or even gigawatts (GW) of power capacity.

However, the AEL technology requires additional improvements in terms of performance and cost reduction from materials to improved balance-of-plants components, control strategies and systems. Research and innovation implementing novel solutions is therefore needed.

These will serve as an outcome to sustain the improvement of the cells and stacks, of the manufacturing processes, of the supply chain support, and will provide an impact on both technology CAPEX and OPEX, as well as the TCO. The R&I activities will consist of a direct support to meet the targets of the SRIA in terms of technology performances, including reaching the targets indicated by the European Hydrogen Strategy, and in order that the technology provides better business cases and integrate better into the specific use cases.

Although AEL is an industrially well-established technology, it presents still some weaknesses when compared to PEM technology. The maximum current density of AEL stacks is generally lower, resulting in bulkier stacks and systems, the dynamic response of AEL is slower, and the minimum current density is limited by safety issues related to gas crossover. However, one of its strengths is the possibility of avoiding the use of expensive and scarce PGM, although many of the large AEL installations that enter service before 2025 are going to rely on AEL technology that includes significant amounts of PGM.

Project results are expected to contribute to all of the following expected outcomes

• Improve the competitiveness of the expected solutions versus the state of the art today in the market;
• Keep the EU specific sector of AEL in the forefront of international competition;
• Improve the electrolyser’s performances (e.g., in terms of current density, dynamic behaviour) and contribute to the achievement of the SRIA KPIs at the level of system and stack (as per Annex 2 Table 2 State-of-the-art and future targets for hydrogen production from renewable electricity for energy storage and grid balancing using alkaline electrolysers);
• Reduce CAPEX and OPEX of the stack by introducing better performances and improved novel components of the cell and related parts.

Project results are expected to contribute to the following objectives and KPIs of the Clean Hydrogen JU SRIA. At least one of the following KPIs should be improved while maintaining the others at the present state of the art (SoA):

• With the aim to reduce the CAPEX, increase the cell current density (minimum 1.2 A/cm2 @ < 2V). Alternatively, as a means to reduce the OPEX, improve the conversion efficiency (nominal electric consumption <48 kWh/kg @ <2V per cell). The different specific conditions should be demonstrated, and the nominal operating point of the stack being optimised considering overall performance, stack lifetime and the TCO, among others;
• Achieve a degradation rate <0.1%/1000h, measured as % efficiency at lower heating value (LHV) and technology reliability;
• Reduce CAPEX of the stack down to 150 €/kW and OPEX to 35 €/(kg/d)/y;
• Avoid the use of PGM and other CRM to ensure the scalability of the technology.

Additional objectives maybe also targeted such as:

• Improve the dynamic behaviour in cold ramp up and partial load, with higher flexible operation in line with the SRIA KPIs for ‘Flexible electrolyser operation’;
• Improve operation range, especially at low power (crossover, safety, etc.) at the same performances of the best-in-class technology (e.g. 10-100% PEMEL);
• Decrease the hydrogen and oxygen cross flow phenomena between the anode and cathode side, at a safety standard 50% lower explosive limit (LEL).

This topic aims at advancing AEL technology by improving performances and reducing costs. AEL technology, despite the high maturity of the proposed market solutions, can be improved in order to keep the EU electrolyser industry at the forefront and to support the achievement of the EU performance and cost targets, widening the range of applications where renewable hydrogen produced by AEL could be deployed to support decarbonisation efforts. Anyway, improved performances and solutions will add margins to this target and a better satisfaction of the specific challenge.

The topic aims to facilitate the integration of innovative lab scale developments in the alkaline electrolysis technologies landscape into pilot industrial scale systems for their validation and further escalation into industrial MW scale systems.

The successful proposal should be able to test and validate in a lab and in a relevant environment the targeted innovative parts or components.

The project should explore some of the following innovations: ​

• New electrocatalysts and electrode materials for alkaline water electrolysis operating at high current density and high energy efficiency based on non-platinum group metals, and preferably on non-critical materials;
• Novel concepts of porous transport electrodes free of precious metal coatings with integrated micro-porous-layer and electrocatalysts;
• Explore new electrode production technologies for more efficient mass production (e.g., advanced electroplating, plasma spraying, physical vapor deposition), combined with development of electrocatalysts for alkaline water electrolysis;
• Improve the separators and/or (microporous) membranes, reaching higher ionic conductivities (enabling higher current densities), improved mechanical properties (enabling thinner membranes), lower gas cross-over (enabling operation at lower load points without safety issues)​;
• Realise the novel proposed AEL short stack at the scale of at least 10 kW, with a minimum cell area of 100 cm² and at least 10 cells for the stack, validating in a laboratory environment the specific performance targets;
• Investigate the potential to increase the temperature to a higher operating window. Develop new alkaline electrolysis systems operating at high temperature, validated at small scales, to improve the operational temperature and energy efficiency (e.g., over 95°C and below 48 kWh/kg);
• Advanced thermal management to shorten start-up time from warm stand-by, (e.g., by intelligent heat storage or insulation schemes);
• Reduce the use of noble metals and critical raw materials, improving the life cycle assessment aspects;
• Moving a step forward with respect to testing procedures and standardised qualifying tests (e.g., considering results from Qualygrids project as well as referring to JRC standardised protocols).

Taking advantage of JRC EU harmonised protocols^[1] for testing of low temperature water electrolysis, it will help updating the standardised testing protocols representative of validating the expected outcomes. This would involve laboratory-based testing of the different integrated improvements into cells and stacks.

Consortia are expected to build on the expertise from the EU research and industrial community to ensure broad impact by addressing several of the aforementioned items.

It is expected to have at least one alkaline electrolyser’ manufacturer as a member of the consortium, to exploit the results and foresee a scaling up of the validated solution.

Proposals are expected to collaborate and explore synergies with the projects supported under topics HORIZON-JTI-CLEANH2-2023 -07-02: ‘Increasing the lifetime of electrolyser stacks’ and HORIZON-JTI-CLEANH2-2022-07-01: ‘Addressing the sustainability and criticality of electrolyser and fuel cell materials’.

Applicants are encouraged to address sustainability and circularity aspects in the activities proposed.

Activities developing test protocols and procedures for the performance and durability assessment of electrolysers and fuel cell components proposals should foresee a collaboration mechanism with JRC (see section 2.2.4.3 "Collaboration with JRC"), in order to support EU-wide harmonisation. Test activities should adopt the already published EU harmonised testing protocols^[2] to benchmark performance and quantify progress at programme level.

Activities are expected to start at TRL 3 and achieve TRL 5 by the end of the project -see General Annex B.

The JU estimates that an EU contribution of maximum EUR 2.50 million would allow these outcomes to be addressed appropriately.

The conditions related to this topic are provided in the chapter 2.2.3.2 of the Clean Hydrogen JU 2023 Annual Work Plan and in the General Annexes to the Horizon Europe Work Programme 2023–2024 which apply mutatis mutandis.

[1] https://op.europa.eu/en/publication-detail/-/publication/bbbeba00-ee82-11eb-a71c-01aa75ed71a1/language-en

[2] https://www.clean-hydrogen.europa.eu/knowledge-management/collaboration-jrc-0_en