Green industrial Hydrogen

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.


Project Overview

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 will be 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 high-purity ‘green’ hydrogen at electrical efficiency of minimum 84 %LHV.

In parallel to the prototype testing operation, a singular stack of the SOEC technology 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.

Technical Objectives


Electrolyser scale-up to 720 kWel,AC producing 200 Nm³/h (18 kg/h)


Electrical electrolyser efficiency up to 84 %el,LHV (< 40 kWhel,AC/kg)

13,000 operating hours

< 13,000 operating hours at system level with a proved availability of < 95 %

20,000 operating
hours at
stack level

< 20,000 operating hours at stack level

hot start

Demonstrate hot start from minimum to maximum power in < 5 mins

>100 tons of
green hydrogen

Produce >100 tons of green hydrogen at under 7 €/kgH2


Reduce electrolyser CAPEX to <4,500 €/(kgH2/d)


Provide techno-economic studies for further market deployment



Create viable technology

Create viable technology by demonstration in a complex industrial environment

Assess CO2

Assess CO2 avoidance potential of a hydrogen-based European steel industry

green hydrogen

Provide significant share of green hydrogen to the iron-and-steel works

purchasing on

Evaluate situation on purchasing renewable electricity and green H2 certification

Consortium Partner