H2Giga - Oxysept

Editors:                           Montadhar Guesmi, Johannes Manthey

Duration:                         09/2021 until 03/2025

Funding institutiton:      Bundesministerium für Bildung und Forschung (BMBF)

Partner:                            Linde AG, ITM Linde Electrolysis GmbH,
                                          Helmholtz-Zentrum Dresden-Rossendorf

Project goals of the flagship project H2Giga

• Currently, electrolyzers are largely manufactured manually.
• The goal of the National Hydrogen Strategy is to build up 5 gigawatts of electrolysis capacity by 2030.
• This requires efficient, durable, robust, low-cost and scalable electrolysers.
• The goal of the H2Giga project is to upscale and develop serial production of electrolysers.
• All three types of electrolysis are considered (technology open):
  • PEM electrolysis
  • Alkaline electrolysis (AEL)
  • High temperature electrolysis (HTEL)
• There are 30 alliances with a total of 130 partners, each of which focuses on different details.

Goals of the Sinewave alliance

• The Technical University of Dresden is part of the Sinewave alliance, which aims to develop more efficient proton exchange membrane (PEM)-electrolysis systems.
• This will involve the realization of high current densities (about 4 A/cm²) for the cost-effective production of large quantities of green hydrogen, as well as the reduction of stack energy consumption to less than 52 kWh/kg H₂.
• High current densities give rise to new and thus far misunderstood operating ranges
  • Changed bubble formation due to higher supersaturation
  • High void fractions (up to 50%)
  • significant temperature increases in the ultrapure water circuit

Goals of the subproject Oxysept

• Oxysept is one of the subprojects of Sinewave. Here, the two-phase flows forming in the anode circuit will be investigated.
• In addition, the development of technologies for the optimization of oxygen separation and cooling takes place.
• In this context, the overall efficiency is to be improved through
  •  a recovery of the by-product oxygen
  •  a recovery of heat

Goals of the subproject of the Chair of Energy Process Engineering

• The contribution of the Chair of Energy Process Engineering in Oxysept consists in the investigation of heat transfer and bubble behavior in a plate heat exchanger with two-phase flow (water and O₂₎ from the ultrapure water circuit of the PEM electrolysis.
• For this purpose, experimental and numerical investigations are carried out and a mutual comparison of the results is made.
• This will lead to the derivation of a digital twin and the generation of design proposals for plate exchangers.

Source: https://www.wasserstoff-leitprojekte.de/leitprojekte/h2giga