Why hard-to-abate industries need renewable hydrogen?

The transition to a low-carbon economy is often associated with renewable electricity. Solar panels, wind farms and the electrification of transport have become some of the most visible symbols of the energy transition. However, electricity alone will not be enough to decarbonise every sector of the economy.

Some industrial activities require high-temperature heat, chemical feedstocks or energy carriers that are difficult to replace through direct electrification alone. This is particularly relevant for sectors such as steel, glass, chemicals and petrochemicals, which are often referred to as hard-to-abate industries because reducing their greenhouse gas emissions presents significant technical and economic challenges.

As governments and industries seek pathways towards climate neutrality, renewable hydrogen is increasingly being recognised as one of the technologies that could help address these challenges.

Why are some industries difficult to decarbonise?

Many industrial processes are designed around fossil fuels, either as energy sources or as raw materials within the production process itself.

This is particularly true for sectors such as steel production, chemicals manufacturing and oil refining, where hydrogen already plays an important role or could become part of future low-carbon production routes. Renewable hydrogen is also attracting growing interest in heavy transport, aviation and shipping, and is increasingly being explored in the context of long-duration energy storage.

Although the specific challenges differ from one sector to another, they all share a common objective: reducing emissions while maintaining performance, reliability and competitiveness.

Why renewable hydrogen?

Hydrogen is already widely used as a raw material in industrial sectors such as refining and chemical production. For example, hydrogen can be used in steel processes to obtain iron through the direct reduction of iron ore. The challenge is that most hydrogen produced and used by these industries today still comes from fossil-based sources (grey hydrogen), resulting in significant greenhouse gas emissions.

Renewable hydrogen offers an alternative pathway, as it can bridge the gap between intermittent renewable generation and consistent energy demand. Produced through water electrolysis powered by renewable electricity (green hydrogen), it can help reduce the emissions associated with hydrogen production while supporting decarbonisation efforts in these sectors where hydrogen can be used not only as a raw material, but also as a fuel for combustion or to generate electricity, depending on the needs.

For many of these applications, the question is no longer whether hydrogen can play a role, but how sufficient quantities of renewable hydrogen can be produced in an efficient and economically viable way.

What makes renewable hydrogen challenging for hard-to-abate industries?

The investment required to produce green hydrogen is still high compared with purchasing grey hydrogen. At the same time, the direct production of green hydrogen can be intermittent due to renewable energy availability, while industrial processes may require a continuous and predictable supply.

Hydrogen production therefore needs to be effectively matched with industrial demand. Decoupling green hydrogen production from its use requires additional investment in storage or specific infrastructure for hydrogen transport that may not currently be available.

How DESIREE is contributing

DESIREE focuses on advancing Solid Oxide Electrolyser (SOEL) technology. SOEL has been identified as a promising solution for producing hydrogen in hard-to-abate industries, since it operates at high temperatures and can therefore take advantage of waste heat from industrial processes. By coupling high-temperature electrolysis with process waste heat, operating costs and, consequently, hydrogen production costs can be reduced. In addition, SOEL offers the highest efficiency among current electrolytic hydrogen production technologies. The project takes a holistic approach that addresses challenges at cell, stack, system and control levels, with the aim of improving the reliability, endurance, efficiency, operational flexibility and sustainability of renewable hydrogen production.

To achieve this, DESIREE is developing advanced electrode materials, improved glass-ceramic sealing technologies, novel heat exchanger solutions, integrated thermochemical hydrogen compression, dynamic control strategies and circular approaches for critical raw materials. These innovations will be integrated into an advanced 40 kW multi-stack SOEL prototype designed to demonstrate improved performance and durability under relevant operating conditions.

By improving reliability, efficiency, operational flexibility and system integration, DESIREE aims to contribute to making renewable hydrogen production more efficient, reliable and sustainable. These advances are expected to support the development of hydrogen production systems capable of meeting the growing demand anticipated across multiple industrial sectors, while contributing to lower hydrogen production costs and improved competitiveness.

Within DESIREE, Spain’s National Renewable Energy Centre (CENER), the Aragon Nanoscience and Materials Institute (INMA), Politecnico di Torino, Genvia, the Fraunhofer Institute for Silicate Research ISC, Bosal, EIFHYTEC, Commissariat à l’Énergie Atomique et aux Énergies Alternatives (CEA), VTT Technical Research Centre and Zabala Innovation are working together to advance Solid Oxide Electrolyser technologies and support the future deployment of renewable hydrogen across industrial applications.