A new European research initiative is developing high-efficiency electrolysis technologies to produce renewable hydrogen from water in a more "sustainable, cost-effective, and efficient way", using advanced and responsible approaches to reduce carbon dioxide emissions.
Despite its potential, hydrogen remains largely carbon-intensive. According to the International Energy Agency (IEA)’s Global Hydrogen Review 2023, global hydrogen production exceeds 95 million tonnes annually, yet only around one percent is produced through low-emission pathways.
Most hydrogen is still generated through fossil-based processes, resulting in substantial greenhouse gas (GHG) emissions and limiting its contribution to climate neutrality. The Development of Enhanced SOEL Components for Improved Reliability and Endurance (DESIREE) project aims to overcome these barriers by advancing the Solid Oxide Electrolyser (SOEL) technology.
Operating at high temperatures, SOEL systems enable highly efficient water electrolysis and offer strong potential for integration with renewable electricity and industrial heat sources.
The project is coordinated by CENER, Spain’s National Renewable Energy Centre, and involves twelve organisations from six European countries – Spain, France, Germany, Italy, Belgium, and Finland – Consejo Superior de Investigaciones Científicas (CSIC), Universidad de Zaragoza, Politecnico di Torino, Genvia, Fraunhofer-Gesellschaft, (through the Institute for Silicate Research ISC and the Center for High Temperature Materials and Design HTL), Bosal, Bosal Energy, EIFHYTEC, Commissariat à l’Énergie Atomique et aux Énergies Alternatives (CEA), VTT Technical Research Centre of Finland and Zabala Innovation.
Together, these entities cover the full hydrogen value chain, from materials and electrochemistry to system integration, sustainability, communication and potential future exploitation.
Design, build, and validate a multi-stack prototype system
With a total budget of nearly EUR 4 million, the 42-month project is supported by the Clean Hydrogen Partnership and co-funded by the European Union under the Horizon Europe programme.
DESIREE will design, build, and validate a 40-kilowatt multi-stack prototype system, building on state-of-the-art stack technologies and focusing on their optimisation, integration, and operational performance at the system level.
The project addresses durability, efficiency, and circularity challenges by optimising materials, sealing solutions, and overall system architecture within existing stack technologies.
The prototype will combine high-temperature electrolysis with thermochemical hydrogen compression, enabling the direct supply of pressurised hydrogen without additional electrical compression.
The system is expected to achieve efficiencies above 85 percent representing a gain of over 15 percent compared with current electrolysis technologies and a key step towards lowering the levelised cost of hydrogen.
Setting a new state-of-the-art
Although SOEL technology is already recognised for its high efficiency, widespread deployment is limited by long-term degradation mechanisms, material constraints and challenges related to dynamic operation under variable renewable energy inputs.
DESIREE addresses these limitations through a holistic, system-level approach. At the cell and stack level, the project will develop advanced electrodes enhanced with nanoscale materials to improve electrochemical performance and reduce operating temperatures.
New glass-ceramic sealing systems with improved thermal and chemical stability will extend stack lifetime under demanding operating conditions.
In parallel, DESIREE will establish recycling routes for critical raw materials such as nickel (Ni), cobalt (Co), lanthanum (La), and strontium (Sr), reintegrating recovered materials into new components.
These material developments are complemented by efforts to enhance long-term stability, enable lower operating temperatures and ensure compatibility with system-level integration.
At the system level, DESIREE will introduce a modular, compartmentalised architecture that enhances operational flexibility, simplifies maintenance and improves thermal management.
Waste heat recovery, supported by advanced heat exchanger design, will be used to drive hydrogen compression, and advanced control strategies and power electronics will enable stable operation in renewable-energy-based grids.
Impact on energy systems and society
DESIREE contributes to the development of highly efficient energy conversion technologies with direct applications in hard-to-abate sectors such as steelmaking, chemical production and renewable fuels for mobility.
DESIREE directly supports the goals of the European Green Deal, the Fit for 55 package and the Clean Hydrogen Partnership, contributing to the European Union’s commitment to cut greenhouse gas emissions by at least 55 percent by 2030 and achieve a fully decarbonised economy by 2050, said project coordinator Iñigo Garbayo, Manager of the Hydrogen Area at CENER’s Grid Integration Department.
Beyond Europe, DESIREE’s outcomes are expected to support global decarbonisation by enabling better integration of renewable electricity with hydrogen-based energy conversion systems, reducing dependence on critical raw materials and fostering sustainable supply chains.
The project also places strong emphasis on skills development, training and gender-inclusive participation.
