Skip to main content

Green Industrial Hydrogen via steam electrolysis

Periodic Reporting for period 2 - GrInHy2.0 (Green Industrial Hydrogen via steam electrolysis)

Reporting period: 2020-07-01 to 2021-12-31

Clean Hydrogen from renewable energies is key to a successful cross-sectoral energy transition enabling the EU’s low-carbon economy goal in 2050. However, access to renewable electricity will be a limiting factor in the future and energy efficient technologies will still be important. Due to a significant energy input in form of steam preferably from industrial waste heat, High-Temperature Electrolysis based on Solid Oxide Electrolysis Cells (SOEC) achieves outstanding electrical efficiencies.

Essential element of the GrInHy2.0 project is to produce hydrogen the most energy efficient way while increasing the technological maturity of the High-Temperature Electrolyser (HTE). Although starting with hydrogen production for today’s steel annealing processes, GrInHy2.0 marks an important milestone towards a hydrogen-based, low carbon European steel industry. Here, hydrogen has the potential to reduce today’s process related CO2 emissions by more than 95 %.

The Salzgitter companies Salzgitter Flachstahl GmbH and Salzgitter Mannesmann Forschung GmbH together with the partners Sunfire GmbH, Paul Wurth S.A. Tenova SpA and the French research centre CEA will work together at the world’s most powerful HTE for the energy efficient production of hydrogen. Further, the consortium will contribute to a detailed analysis of the potentials of renewable hydrogen in the iron-and-steel industry as well as the in-depth understanding of SOEC long-term behaviour on stack level.

With the first implementation of a High-Temperature Electrolyser of the Megawatt-class, GrInHy2.0’s prototype will produce 200 Nm³/h of hydrogen at nominal power input of 720 kWAC. The HTE system consists of up to eight modules with 720 or 1,080 SOECs each, i.e. 24 or 36 stacks, respectively.

As in the predecessor project GrInHy, the prototype is fully integrated into Salzgitter’s steelmaking operations and will run on steam from waste heat of the steel production. By the end of 2022 it is expected to have been in operation for at least 13,000 hours, producing a total of around 100 tons of ‘green’ hydrogen at electrical efficiency of minimum 84 %LHV (electrolyser).

In parallel to the prototype testing operation, a single SOEC stack will set new standards in long-term testing with a test bench operation of at least 20,000 hours. The test will not only show the technology’s increased robustness but also provide potential starting points for further improvement.

In a broader perspective, the project will also deliver answers on how to avoid CO2 emissions in the European steel industry by switching to a hydrogen-based primary steelmaking and what it takes.
Since its start in January 2019, the project progressed with minor changes according to the work plan. The GrInHy2.0 project is divided into six Work Packages.

The first reporting period mostly covered initial and preparational work: Sunfire manufactured the High-Temperature Electrolyser with a target capacity of 720 kWAC producing of 200 Nm³/h and Paul Wurth assembled the Hydrogen Processing Unit consisting of compressor and dryer. In the meantime, SZFG prepared the installation site. For the parallel stack testing, CEA installed and commissioned the test bench for the 20,000- hours testing period. Besides these activities, the initial work also included Tenova’s pre-study about the potential of hydrogen usage in integrated steel works and the development of an operational approach to comply with the green hydrogen definition of the CertifHy scheme.

Accompanied by techno-economic studies, the last 18 months (2nd period) were mainly dedicated to the commissioning and operation of the GrInHy2.0 system prototype, on one hand, and long-term stack testing, on the other.

The first hydrogen produced, that was passing the quality criteria, was injected during the commissioning stage in December 2020. As of December 2021, the prototype system reached 5,600 hours of operation while producing and injecting 42 t of hydrogen.

Thus, the system reached a time availability of ~ 80 %. System downtimes were mostly due to hardware and software optimisations and installations of replacement HTE modules.

Over the year 2021, the production capacity increased to a production rate of 170 Nm³/h with an HTE electrical efficiency of >84 %LHV. The nominal production capacity of 200 Nm³/h will be reached in Q1/2022.

With 12 months remaining, all operational targets are within reach.
While in the first period the commissioning of the test bench took longer than expected, the stack-testing had another setback in the second period: Due to an irregular laboratory-wide gas shutdown, the SOEC stack, which had already been in operation for 4,500 hours, was destroyed. The current stack was started in early March 2021, and is closing in on 7,000 h of operation, with promising results. However, while more than 20,000h of total testing time will have been acquired on the Grinhy2.0 test bench by the end of 2022, the milestone of 20,000 h of operation on a single stack can no longer be reached within the frame of the project.
The test will be extended until the end of 2023 in the frame of the MultiPLHY project.
Despite its advantages, HTE technology still shows a lower degree of maturity compared to water electrolysis technologies. A specific challenge of the project is to bring HTE closer to the maturity level of PEM and alkaline electrolysers. In this context, GrInHy2.0 has already achieved great contributions. The project focuses on designing and manufacturing the most powerful SOEC system and on operating it at an integrated iron-and-steel works. Therefore, the project addresses the progress against state-of-the-art from several angles:

This includes the technology itself at stack and system level, as well as the integration of green hydrogen from a decentralised electrolyser into the processes of the European steel industry.

Through a multitude of improvements (e.g. efficiency, durability, costs), GrInHy2.0 will significantly impact the competitiveness of green hydrogen production compared to fossil alternatives such as steam methane reforming, as well as the competitiveness of green hydrogen used in Direct Reduction compared to traditional coal-based reduction processes.

Furthermore, GrInHy2.0 will change the perception of using green hydrogen in industrial processes by demonstrating a viable large-scale application for the use of renewable energy. The generated information on the operational, technical and financial performance of the HTE itself and the illustration of the integration into the commercial and technical processes of the customer will ensure that the results have maximum impact for further market deployment.

The aim is to create a viable market by demonstrating how HTE can work in a complex industrial environment improving carbon reductions over existing technologies. Therefore, the project results will be disseminated to decision makers that are likely to commission similar facilities in the near future (potential customers in the same or other relevant industries) and those who provide supportive policies for the technology (e.g. national governments and people of public interest).

GrInHy2.0 will provide a significant share of green hydrogen to the iron-and-steel works and will in addition provide an assessment on the EU market based on the CO2 avoidance potential of hydrogen for the European industry as a whole.
Status of Installation Site, May 2020
GrInHy2.0 Project Concept
Status of Steam Electrolyser Unit, May 2020
Status of Hydrogen Processing Unit, May 2020