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Reliable operation of fuel cells

Reliable operation of fuel cells

System solutions for hydrogen supply and water separation

Fuel cell systems have much fewer components compared to other energy converters such as internal combustion engines, but even they need pumps and valves as well as the corresponding sensors. Thus, among other things, precise hydrogen dosing, safe hydrogen cut-off and precise water separation in the anode circuit of the fuel cell must be guaranteed.

The basic structure of a PEM fuel cell is relatively simple (see Fig. 3). It consists of two electrodes that are separated by a membrane. On the anode side, the energy source hydrogen is supplied as fuel and on the cathode side, oxygen from the air is supplied as an oxidizer. The membrane itself is coated on both sides with catalyst material. This ensures that electrons are split off from the hydrogen molecule on the anode side. The membrane is permeable to the resulting protons, so they can pass through and make it to the cathode side, in order to be able to react there with oxygen from the air to form water.

The electrons that split off on the anode side travel to the cathode via a closed electrical circuit. Used in this are the electrical as well as thermal energy. In a vehicle, this electrical energy can then be used, for example, to charge a battery or directly for the electric drive. In the stationary area, for example for the self-sufficient energy supply of a house or building complex with electricity and heat, the fuel cell ensures emissions-free living with renewable energies. When used to secure critical infrastructures such as signal boxes or data centers, hydrogen fuel cells are used instead of diesel generators and enable the use of CO2-neutral energy.

Safely dose hydrogen
So that PEM fuel cells like the HyStack® 400 from Proton Motor Fuel Cell GmbH (see Fig. 2) can be operated without any problems, among other things, components for the hydrogen supply and water separation are required that meet the fluid control demands of the manufacturer and feature defined interfaces to the fuel cell stack module. Robert Baustädter (see Fig. 1), Fuel Cell Engineering division at Proton Motor, stated: “Such systems are essential for the functioning of the fuel cell, because they regulate the supply of hydrogen at the anode input and are also responsible for the safety shutdown. At the anode output, they must ensure gas purging and water separation.” Only then can several of these stacks (21.3 to 49.7 kW) be connected together and in HyShelter® (see fig. on p. 4) sold to customers as a turnkey container solution.


Fig. 2: The HyStack® 400 module from Proton Motor, Source: Proton Motor

The Bavarian company developed solutions for this together with Bürkert Fluid Control Systems, an expert for special fluidic components, whose materials are tailored to the special requirements of these areas of application and form the basis for a wide variety of system solutions. Among other things, compact blocks were developed for both anode supply and water separation, which are attached directly to the stacks using fluidic screw connections and require little installation space (see Fig. 1). „ The media adapter plates, which we have a partner produce using 3D printing, are more than just a mechanical interface. They are a multifunctional component that monitor the pressure and temperature of the individual stretches as well as ensure the proper tempering of the overarching system,” reported Robert Baustädter. The fuel cells are quickly ready for operation even in sub-zero temperatures.

Control valves in the anode block
In the anode block, a servo-controlled piston valve provides safety shut-off for the hydrogen supply. An integrated pressure sensor checks for the target pressure. As a redundant safety component, a pressure switch is also installed. To increase pressure and leakage safety, the plug and core guide tube are welded together. The shape and surface quality of the housing enable maximum flow values. The coils are pressed with chemically highly resistant epoxy.

A second valve – a direct-acting proportional valve – assumes the pressure control for the hydrogen. It is, with its integrated cut-off function, likewise tightly closing. For use in fuel cell systems, suitable plug-in (cartridge) and flange housings as well as magnetic coils with automotive connectors of protection class IP6K9K are also available.

Water and hydrogen separation
In fuel cell systems, the hydrogen introduced into the anode is never completely used up. In a recirculation cycle, the unused hydrogen is not wasted, but is fed back into the stack. At the anode output, the water separator with two integrated valves ensures, on the one hand, the flushing process of the fuel cell system and, on the other, the separating out of the water evolved in the stack during the chemical reaction.

For the two direct-acting plunger valves, the plug and core guide tube are welded together to increase the pressure and leakage safety. The sealing materials are adapted to the application, because the valves not only have to work precisely and reliably, but also have to be tailored to the specific area of application. With hydrogen, for example, the materials used must not become brittle and must not corrode when used with deionized water.

Robert Baustädter summarized: “For the HyStack 200 with outputs from 4 to 11 kW that is currently being developed, in principle the same fluidic systems could be used, just with smaller nominal valve sizes.”

Business operations of Proton Motor are shutting down
At the time of going to press, it was questionable what would happen next with the Puchheim-based company. Due to financing problems, employees are currently being laid off and new investors are being sought (see p. 7).


Fig. 3: Basic structure of a fuel cell, Source: Bürkert Fluid Control Systems

Authors: Sven Geitmann
Dominik Fröhlich, Jan Beranek, both at Bürkert Fluid Control Systems, Ingelfingen, Germany

Hydrogen for racing cars

Hydrogen for racing cars

Formula Student relies on H2

In the summer of 2025, the first hydrogen vehicles will compete against vehicles with conventional drive systems at the Red Bull Ring in Spielberg, Styria, Austria. To ensure that both fuel cells and combustion engines can be used there, Formula Student Austria, in cooperation with other race organizers, has published corresponding H2 regulations that will enable student teams to design, build and race hydrogen-powered racing cars in the future.

Formula Student Austria (FSA) is the Austrian event of the Formula Student racing series and has been held every year since 2009. This racing series enables young, dedicated students from universities and universities of applied sciences from all over the world to demonstrate their knowledge, design and development skills as well as their organizational and commercial talents in several different disciplines.

Formula Student Austria takes place annually at the Red Bull Ring in Spielberg. In 2025, 58 international teams from almost 20 different nations and more than 1,600 students will be taking part. Different disciplines challenge the students on several levels. In addition to the obligatory technical scrutineering, the five dynamic disciplines are all about the speed and reliability of the racing cars they have designed and built themselves. The three static disciplines include the engineering design and thus the evaluation of the construction of the respective vehicle by international jurors. In addition, the business plan and marketing strategy are evaluated, as is the cost breakdown.

Technological openness for the future
As Formula Student is traditionally divided into two classes, one with a combustion engine (CV – combustion vehicle) and one with an electric motor (EV – electric vehicle), Formula Student Austria now also gives students the opportunity to develop and build hydrogen vehicles. The organizer is concerned with technological openness. In order to enable the participation of vehicles with H2 drive systems at the 2025 event, Formula Student Austria started to look into the topic almost three years ago.

Maximilian Jauk, Head of Design at Formula Student Austria, reports: “Our motivation is that we want to offer future engineers the opportunity to deal with the topic of hydrogen outside of their studies. This topic is becoming increasingly important for employers from various industries. We are aware that alumni of Formula Student teams do not only apply for jobs in the automotive industry, but that hydrogen expertise is also of interest to employers in the fields of commercial vehicles, energy infrastructure and hydrogen production.”

Hydrogen Concept Challenge
Since 2023, there has been a Hydrogen Concept Challenge in cooperation with two other Formula Student events, FS Alpe Adria (Croatia) and FS East (Hungary). The Hydrogen Concept Challenge is an ideas competition in which students present their concepts for Formula Student vehicles with a fuel cell or combustion engine to experts from the industry and judges from FSA. The teams engage in the topic of hydrogen for the first time and think about future concepts. Teams from Vienna, Deggendorf and Stuttgart have already taken part in Formula Student Austria 2023.


Fig. 2: Everything in youthful hands

In 2024, the Formula Student events in Portugal and France as well as Formula Future in Germany were also won over to the topic of hydrogen. Together with these events, the Hydrogen Concept Challenge has now been revised to create an even closer link to the actual construction of hydrogen vehicles. The teams were asked to think about the arrangement of the components in order to define installation space for the additional components required, such as the tank or fuel cell.

Furthermore, an analysis was required to examine the effects of the new drivetrain and the additional weight of the heavy high-pressure tanks on lap times compared to conventional Formula Student vehicles. In addition, the tank system and the cooling system were to be analyzed and the tank, battery and fuel cell were to be dimensioned. Finally, the costs should also be taken into account.

This year, the team from FH Campus Wien presented their concept for converting a conventional combustion engine to run on hydrogen and for integrating the H2 components into a Formula Student vehicle. Teams from the University of Vienna and the University of Karlsruhe presented concepts with fuel cells. German, Swiss and Dutch teams presented themselves at other events.

Support from the business world
The INNIO Group, a globally active company headquartered in Tyrol, was the first partner on the topic of hydrogen, without whose support the Hydrogen Concept Challenge at FSA would not be possible. As a leading provider of energy solutions and related services and a pioneer in green technologies, the INNIO Group supports its customers in moving towards net zero. The company has more than 50 years of experience in the conversion of renewable energy sources and already offers engines with a “ready for H2” option.

Targets for 2025
After two successful years with the Hydrogen Concept Challenge, the first version of the Hydrogen Rules for 2025 was published in July 2024. With the help of feedback from industry, H2 experts and interested teams, the set of rules defines the boundary conditions that teams must adhere to in order to ensure safety and fairness.

The vehicles may have a maximum of 2 kg of hydrogen on board. The hydrogen is stored at a pressure of up to 350 bar in tanks certified in accordance with the standards. To ensure safety, sensors must be implemented that switch off the vehicle and in particular the hydrogen supply in the event of a malfunction.

“We are currently considering whether we can offer standard tanks in collaboration with a company in order to reduce costs for the teams, make procurement easier, increase safety and give us more options for refueling. For example, a swap system might be conceivable, similar to that used in gas barbecues. According to the regulations, the tanks should be removable within 15 minutes so that refueling outside the vehicle is possible and the teams can work on the vehicles with the tank removed. This ensures that there are no significant amounts of hydrogen in the car when it is in buildings, such as the pit lane of the Red Bull Ring or the workshop at the university,” says Paul Mayr-Harting, founder of the engineering firm HoKiTech and the main person responsible for the technical approval of the racing cars at Formula Student Austria.

To facilitate the switch to hydrogen, the Formula Student teams are allowed to convert existing combustion or electric vehicles. The focus should be on the commissioning and implementation of a hydrogen-based powertrain. This means that neither a new monocoque nor a new frame needs to be manufactured. The existing chassis and wing package can also continue to be used.

In order to compensate for the weight disadvantage of fuel cell vehicles compared to conventional electric vehicles in Formula Student, the teams are allowed to drive with 100 kW instead of 85 kW system power. The teams have a free hand in the selection and dimensioning of the fuel cell and the design of the battery, although at least half of the energy must be provided by the fuel cell in the 22-kilometer endurance race.

The hydrogen-powered combustion vehicles can be equipped with four-stroke engines with a displacement of up to 1.6 liters. Most teams will probably use motorcycle engines and convert them to run on hydrogen. The amount of air drawn in and the amount of hydrogen injected are not regulated. “It is becoming increasingly difficult for existing combustion engine teams to attract partner companies. By switching from fossil fuels to hydrogen, we are also opening up new opportunities for the teams to find long-term sponsors. They are also looking at alternative drive systems and reducing the CO2 footprint for a green future,” explains Christoph Hirt, Event Manager of Formula Student Austria.

Cooperation and networking
For many students, Formula Student is an important part of their studies. The theory they have learned is put into practice, while at the same time teamwork and self-organization are required. International contacts with like-minded people and potential employers can be made at the competitions. At Formula Student Austria, volunteer alumni from student racing teams take care of the professional organization and implementation. If you and your company would like to become part of Formula Student Austria, we look forward to talking to you. You can find our contact details in the box.

The next opportunity to take part in Formula Student Austria will be from July 20 to 24, 2025 at the Red Bull Ring in Spielberg, Austria.

Authors: Romana Močnik, Steffen Schmitt, both Formula Student Austria, Graz

Shortage of skilled workers in the hydrogen economy

Shortage of skilled workers in the hydrogen economy

Various training courses at different institutions

For around five years, the number of employees in the renewable energy sector has been steadily increasing again. Nevertheless, in Germany, it is not at its historic high. That was in 2011, at over 400,000 employees. Due to political and regulatory circumstances, this number fell by around 100,000 workers over the next eight years. The solar industry in particular has recorded heavy losses. Now, it is on the upswing again. Similar to green hydrogen, which is right where the solar industry was 20 years ago.

The hydrogen industry faces the same challenges as other energy sectors: How can companies specifically train specialists for the necessary applications and techniques? Can the foreseeable shortage of skilled workers still be avoided? And do companies actually see a need to train their employees in the areas of the hydrogen economy?

In order to counteract these open questions with offers, various training centers are offering training programs for interested companies. The content is usually based on the essential stages of the H2 value chain. The fundamentals of generation, storage and infrastructure therefore play a central role. Also conveyed are the overarching importance of hydrogen for the energy transition as well as the goals of the German and European hydrogen strategy.

Basic knowledge also includes chemical and physical properties. The training centers thus teach the various technologies for the production and use of the energy source H2, for example in power-to-gas, in gas turbines or fuel cells. In addition, the integration into existing networks, the effects on distribution network operators and the far-reaching applications in the industrial, energy and mobility sectors are being intensively discussed.

Also the issue of safety is covered by many training programs. Most of them teach safe handling of hydrogen, explosion protection and the tightness of hydrogen systems. In some cases, the academies are planning to offer the building sector and heating technologies as well.

But which companies should actually be concerned with the topic of hydrogen now? The main influencing factor here is the energy intensity of a company’s processes. The steel or chemical industries are therefore often mentioned, which require such large amounts of energy that they cannot be electrified. Of course, this also includes companies that are directly involved in the planning of hydrogen projects and the development of the necessary infrastructure.

However, utilities or municipalities can also use hydrogen to expand a city’s energy portfolio in the direction of climate-friendliness and resilience. They are all therefore the target group of further education institutions. “These training courses should ensure cross-departmental awareness and training within the company, as well as be offered for qualified and technical personnel, energy officers, development engineers, production managers, occupational safety, quality control and management,” says Frederike Westenberger from the TÜV-Nord-Akademie.

In this way, basic knowledge about the topic can be conveyed, and future projects can be approached as future qualified on this basis. As particularly critical the training of the technical divisions that deal with research and development may be viewed.

Training for managers

To demonstrate the need for green hydrogen in a company, trained managers and administrators are also needed. They make resources available and support critical divisions. “One of the main challenges here is to reconcile the interests and the different perspectives of the companies and partners involved,” confirms Jan Heinze, managing director of the Hamburger Heinze Akademie. Therefore, in his opinion, managers should acquire deeper, in-depth knowledge.

Interest increasing

Directly “at the beginning of the ramp-up of hydrogen activities, we saw a great willingness to deal with the previously little-known properties and applications of hydrogen,” says Gunter Maetze from the Weiterbildungszentrum für innovative Energietechnologie (WBZU). At the WBZU in Ulm, participants in the area hydrogen mobility gain for example the Zertifikat für Gasanlagen in Fahrzeugen (certificate for gas drives in vehicles) in accordance with standard DGUV-FBHM-099.



Fig. 2: Peter Pioch from WBZU shows an H2 flame with a thermal imaging camera

The Haus der Technik (HdT) is likewise seeing a growing interest. This is motivated by social demands for more sustainability. The aim is to partially or completely change the energy supply. “To keep up with rapid technological developments, people are increasingly turning to us,” confirms Michael Graef, chief editor of the HdT-Journal.

This interest can also be seen at the Heinze Akademie. Since May 2021,135 participants have successfully completed the full-time course there. In the part-time IHK certificate course, 80 module exams were taken in one and a half years. The academy expects an increasing need for further training among engineers by 2027, for masters and technicians as well as commercial workers by 2029.

Framework conditions unsettled

Not all continuing education academies share this view, however: “From our experience, we observe a rather reserved level of interest. Of course, it may be that other offers on the market are more widely accepted. We assume that this is also due to the currently uncertain economic conditions and the wait-and-see attitude of many companies regarding the future development of the hydrogen economy,” says the BDEW-Akademie. Here, the still not clearly defined framework conditions are decisive.

A similar situation is recognized by the TÜV­Nord­Akademie: “There is uncertainty due to a lack of legal and normative foundations as well as the economic viability of projects. These factors lead companies to wait and see whether they will actually invest in hydrogen technology and train their staff accordingly.”

Already a shortage of skilled workers

The reluctance of companies to offer hydrogen training from the bottom up goes hand in hand with the current situation in the labor market of the hydrogen economy. Here, there is already a shortage of skilled workers, but this is a fundamental phenomenon that is not only associated with the growth of this particular labor market. The shortage of skilled workers in the hydrogen economy can be traced back to the fundamental problem that, due to demographic change, there is a shortage of young talent everywhere.

The HdT sees a possible solution in the further qualification of existing staff. The WBZU recognizes that a gap in suitable qualification offers has now been closed for many subject areas with further training opportunities. “Things look a little different in the area of training. Here, the mills are grinding more slowly and it will still be a while before hydrogen topics find their way into curricula everywhere,” says Gunter Maetze.

The demand for qualified specialists will increase in the next few years according to the current trend. “If companies can no longer find skilled workers on the free market, we can further qualify those looking for work through resources and support from the Bundesagentur für Arbeit,” proposes Jan Heinze. This requires, however, some lead time.

H2 ramp-up increasing number of employed people

How labor demand and labor supply will come together for the hydrogen value chain in the coming years is the subject of a study by the Institut für Arbeitsmarkt- und Berufsforschung, a research institution of the Bundesagentur für Arbeit (federal work agency). Using scenario analysis, the influence of green hydrogen on the labor market until 2045 was examined. The scenarios compare the influence of a developed hydrogen economy with the influence of one that is missing.

The results show that the ramp-up of hydrogen has consistently positive effects on the number of employed people. In this scenario, by 2045 it will be an average of around 57,000 people higher than in the reference scenario. In absolute terms, the construction industry in particular is facing a higher demand for labor, which is accompanied by the expansion of renewable energies for the production of green hydrogen and the development of the hydrogen infrastructure.

There are also positive effects in the areas of architecture and engineering firms, technical investigations, childcare and teaching as well as in mechanical engineering. The research report shows more demand for administrative jobs. It becomes clear that there are already bottlenecks in many of these professional groups, which could delay the development of the hydrogen economy.

The study identifies the price of electricity as an important influencing factor and the associated costs of hydrogen and its derivatives ammonia and methanol. With 20 percent lower electricity prices for electrolysis abroad, the gross domestic product (GDP) would be an average of 7.7 billion euros by 2045 and the number of employed people would be an average of around 66,000 higher than in the reference scenario. If electricity prices were 40 percent lower, domestic GDP would be higher by an average of 11.2 billion euros and the number of employed people would be higher by an average of around 76,000 people.

The cheaper hydrogen can be made available, the higher the GDP and employment figures will be. However, it is also important to compare the costs of fossil fuels. If fossil fuels become more expensive, this will have a positive impact on the value of the hydrogen economy and thus on the number of people employed in this area. Government measures could also have a supportive effect here.

The shortage of skilled workers can be addressed

Clear is: The offer of training and further education programs exists. The educational centers offer what addresses the individual important areas of the topic of hydrogen. Nevertheless, the interest from companies is rather mixed. Although the energy industry is clear about the importance of the energy source, the political and economic conditions are a deterrent factor.

The hydrogen industry is probably heading towards the overall shortage of skilled workers that is affecting many sectors of the economy. The study of the Institut für Arbeitsmarkt- und Berufsforschung, however, also makes it clear that there is great economic potential waiting in hydrogen as an energy source. Once the ramp-up really starts, companies will no longer see any reason to hold back – and the shortage of skilled workers can still be counteracted.

Author: Fabian Kauschke

Changes on the horizon

Changes on the horizon

What developments! We are living in turbulent times. Several transformative processes are currently taking place at the same time: Not only the energy, transport and heating transition with the move away from fossil fuels or the social trend towards increasingly autocratic structures, but also the complete transformation of the information and communication sector with AI (artificial intelligence). It is therefore not only all industrial companies that are faced with the question of how their energy supply can be CO2-free by 2045. We are not only faced with the question of how we can end wars and strengthen democratic structures. The transformation process affects the whole of society – worldwide. Newsrooms, media houses and press agencies must also face new challenges and, for example, find a way of dealing with computer-generated information and fake news – whether they like it or not. And of course the advancing climate crisis also plays a decisive role here: Will journalists continue to research live on location and report from there? How many trips will be justifiable in the future from an environmental point of view? How will paper prices and postage costs develop? Will publishers still be needed at all in the future? Will readers still want to receive print copies tomorrow or will other formats be needed in addition to more digital offerings as well as podcasts, videos and webinars? Hydrogeit Verlag has been dealing with all of these questions for years. Originally started as a one-man publishing house, the range of activities has changed considerably since the company was founded in 2004. For some time now, there has been a team responsible for publishing HZwei and H2-international – now around ten people who work part-time. Despite the diligent and sustained commitment of all these players, we are constantly reaching our limits. While the hydrogen sector and interest in H2 and FC topics continue to grow, our offering has remained largely the same in recent years – high quality, as many readers keep telling us – but still focused primarily on the print sector and the printed HZwei magazines. And not really up to date. That may well change. To ensure that HZwei and H2-international continue to be perceived as leading media in the industry in the future, innovations are needed now. In order to enable up-to-date reporting online and to be able to offer more modern formats, appropriate structures and more power are needed. For this reason, we looked around for suitable cooperation partners months ago and found a player in Gentner Verlag that is a perfect fit for us both thematically and structurally. With its “Photovoltaics” and “Renewable Energies” brands, the Stuttgart-based publishing house publishes two important magazines that fit well with our magazine on hydrogen and fuel cells. We have therefore decided to work together from this year onwards in order to be able to cover the energy sector even better together. So you can look forward not only to more up-to-date and comprehensive information, but also to new formats in the future. As a first step, we have increased the frequency of publication. HZwei and H2-international will be published five times a year in 2025 and even six times a year starting 2026. We will also have our own stand at Hydrogen & Fuel Cells Europe in Hanover, where we will be able to interact with you, our readers. Further measures will follow in the course of the year. We look forward to a more intensive exchange and constructive feedback. These are turbulent times and we not only want to accompany them with information, but also actively contribute to shaping them sustainably. Sincerely, Sven Geitmann Editor of H2-international

Hydrogen terminal in Braunschweig

Hydrogen terminal in Braunschweig

Green hydrogen for research

A research environment along the H2 value chain is being created at the Research Airport in Braunschweig. Research is being conducted on green hydrogen production as well as the storage, transportation and use of hydrogen in heavy-duty mobility. Based on designs by Jahn Architektur, a unique H2 research landscape on a real laboratory scale has been created on the approximately 5,000-m2 (54,000-ft2) site, making it a demonstrator of a future energy center in the megawatt range.

The transportation and storage of renewable energy is one of the biggest challenges of the energy transition. One solution is emerging in connection with technologies related to hydrogen as an energy source. The construction of Hydrogen Terminal Braunschweig will create a location for pooling research expertise along the H2 value chain in the megawatt range. The project, funded by the German Ministry of Education and Research (BMBF) with a total funding volume of over 20 million euros, is being implemented as a joint project under the leadership of the Steinbeis Innovation Center Energieplus (SIZ Energieplus), the Technical University of Braunschweig and the University of Hamburg together with the project partners BS Energy and the Fraunhofer Center for Applied Nanotechnology (CAN).

Motivation for the project
The heart of the project is currently the AEM multicore electrolyzer from Enapter with a power class of 1 megawatt, which is the world’s first prototype to bring AEM (Anion Exchange Membrane) technology to Braunschweig. In addition, STOFF2’s innovative zinc intermediate-step electrolysis system for hydrogen production is to be installed on the site in the coming months. In addition to the electrolyzers located outside the building, electrolysis test benches have been set up in the research building to investigate alkaline electrolysis and PEM (Proton Exchange Membrane) electrolysis.

With the various electrolysis technologies, the essential range of existing production approaches for green hydrogen is represented for direct comparison within the hydrogen terminal. As part of the project, research is being carried out to increase the efficiency of all technologies. In addition, the production of hydrogen by (co-)pyrolysis of hydrocarbon-containing feedstocks is being tested and further developed as part of the research project.

Status quo in implementation
The green hydrogen generated with renewable electricity from the electrolyzers is used in various ways. On the one hand, it is used in internal test benches to carry out ageing tests on fuel cell and electrolysis membranes. Secondly, other external (fuel cell) test benches at the Fraunhofer Center for Energy Storage and Systems (Fraunhofer ZESS) and the Niedersachsen Research Center for Automotive Engineering (NFF), which is around one kilometer away, are supplied with the green hydrogen via pipeline.

Parallel to the supply of hydrogen, Fraunhofer ZESS is supplied with waste heat from electrolysis. For this purpose, the temperature level of the waste heat from the electrolysis processes is raised using a high-temperature heat pump and made available via a local heating network. In addition to the use of the hydrogen in the test benches, it is used to test hydrogen storage in the world’s largest metal hydride storage facility, currently operated by GKN Hydrogen.

In addition to being used in test benches, the hydrogen produced on the Hydrogen Terminal site is used to operate a hydrogen refueling station from the manufacturer Maximator. At this filling station, heavy-duty vehicles can be refueled with green hydrogen at a pressure level of 350 bar.

The project is also investigating how the electrolyzers and fuel cells, in conjunction with a large battery storage system (storage capacity: 1.1 MWh) and the solar system, can be used to stabilize the grid when conventional fossil fuel power plants are no longer available.

After the opening ceremony in late summer, the time-consuming commissioning work was then carried out. The high-temperature heat pump from Combitherm, which was designed together with the TGA planner EGS-plan from Stuttgart, is already in operation, as are the redundant propane heat pumps from Viessmann. The ventilation system from Trox and the electrolyzer from Enapter are currently being put into operation. The certified system builder H2 Core Systems from Heide is also being trained on this system and will be able to carry out the construction and commissioning of the Nexus1000 independently in future.

The battery system will be put in operation by SMA by the end of the year. They are working together with the marketer Next Kraftwerke and the Elenia Institute for High Voltage Technology and Energy Systems to investigate the grid-forming properties for voltage and frequency stabilization of the inverter.


Fig. 2: Markus Hartwig (right) and David Sauss (left) with Sebastian Sipp, Managing Director of STOFF2, on the site of the hydrogen terminal in Braunschweig, Source: STOFF2

Green hydrogen with PV on site
In addition to the now mandatory solarization of the roof areas, an agrivoltaic system was installed on the remaining ecological compensation area as a demonstration. Concrete foundations were completely dispensed with and screw anchors were used. This means that the ground-mounted photovoltaic system can be completely dismantled and is also suitable for temporarily usable areas. The amount of electricity generated is not sufficient to cover the electricity requirements of the systems; therefore, currently for the start of operation, certified green electricity is being purchased on the spot market.

In the future, a 3 MWpeak ground-mounted photovoltaic system will be built on the neighboring property. Empty conduits have been laid for this as well as a feed-in field in our medium-voltage customer system. In the long term, direct, local renewables will not be sufficient for green hydrogen certification. To this end, they will conclude further direct supply contracts (PPAs) in order to achieve the necessary full-load hours and production volumes.

Expansion to include intermediate zinc electrolysis
STOFF2 and SIZ Energieplus are currently investigating the integration of a zinc intermediate-step electrolysis on site. This is a new and innovative electrolysis technology. It takes in green electricity over four hours, stores the energy safely in the form of zinc in the electrolyzer and then discharges green hydrogen over 12 to 24 hours. The charging and discharging process can be flexibly controlled. This ensures that, on the one hand, electricity from renewable energy sources is charged when it is available at low cost and, on the other hand, hydrogen is made available exactly when customers need it.

At the hydrogen terminal site in Braunschweig, the zinc intermediate-step electrolysis is intended to further improve H2 supply security in conjunction with the other components. At the same time, this technology is intended to increase the degree of self-consumption of PV electricity.

Hydrogen Terminal Braunschweig has created an innovative learning, training and research environment for hydrogen, which other projects can now dock onto.

Authors: David Sauss, siz energieplus, Braunschweig, Markus Hartwig, STOFF2, Berlin