HTO workshop on technological developments in electrolysis systems | Enagás

We are celebrating the third workshop of the hydrogen technology observatory focusing on technical developments on electrolysis systems. And first of all, let me extend a warm thank you to all the online and in-person attendees for joining us today. And now I have the pleasure of introducing our CEO of Enagás, the promoter of this observatory, who will officially welcome you. Thank you very much.

Thank you, Arturo. Now I am delighted to introduce Vanessa Hill, a key contributor to today's workshop. Dr. Vanessa Hill, PhD in science, is a senior researcher and head of research and development at the Aragon Hydrogen Foundation. Recently recognized with the Remarkable Woman in Renewable Hydrogen 2025 award. Vanessa brings over 20 years of experience in hydrogen technologies, specializing in both high and low temperature water electrolysis. The Hydrogen Foundation of Aragon is a vital partner of the observatory because of its expertise and its relevant trajectory. Therefore, Vanessa will moderate the following round table. Please Vanessa, the stage is yours. Thank you very much.

So thank you Igor for the kind introduction and also thank you Enagás for the invitation to the Aragon Foundation to this workshop today. So as we heard just in the opening, we will facilitate today knowledge and technology exchange and also we will drive forward the key innovations into the electrolyzer systems. We will hear from two speakers, one from Accelera by Cummins and also from Nordex, about two mature technologies: alkaline technology and also PEM technology. But there are also more technologies in the sector. So first I would like to say why electrolysis? As we heard today and we have heard during the few years, electrolysis is a key technology for low emission hydrogen production. Why this is because electrolyzer enables to produce hydrogen that is needed for a future energy market and sector. But also electrolyzers enable linking sectors that were not linked until today.

So before we start with what we discuss today about the challenges and also how is the status of the technology today and the prospects and where we go in this path, let me first give a few words about how is the status today about electrolysis capacity. The electrolysis capacity for dedicated hydrogen production has been growing in the past few years, but the market is true that is moving slower than it was expected. As you know, last year Europe should have had six gigawatts of electrolyzers installed and also the production should be 1 million tons of hydrogen. This is too much. We haven't reached this milestone so far. According to the Clean Hydrogen Monitor from the European Hydrogen Association, today we have almost 400 megawatts of installed capacity and also approximately a thousand tons of hydrogen has been produced. This is not enough. Also in Spain, we have right now a few megawatts of electrolyzers and we might reach a few gigawatts. This is too much and a lot. This is an opportunity for our country, Spain, to attract investment, also to attract electrolyzer manufacturers to our country, also linked to our renewable sources that we have.

In this path about how we see our country and what could be, we should think about electrolyzers from the technology point of view. The electrolyzers are being manufactured today. This is a reality. We can buy these kind of systems, but still there are some challenges and still we could improve these systems. We could improve the systems in regards of the lifetime of the equipment, also regarding reducing the cost, always important if we can save some money is always good, but also improving the efficiency, this is also very important. Apart from this, there are other key innovations that maybe we will hear today and could be related to different modes of operation, could be high pressure for example, or could be other changes in the standard operation conditions of these systems. I said in the beginning we will talk about alkaline and about PEM technologies, but there are more technologies.

The reason we decided to go to these two is because they are the most mature technologies in the market right now. There are also other technologies that some years ago were very low in scale and just in the beginning, for example solid oxide electrolysis. But it's true that this technology is quickly scaling up its maturity. For example, in April 2023, just to give you a few numbers, 2.6 megawatts of solid oxide electrolyzer was installed in Netherlands in a refinery from Neste and it became the biggest at that time, but only a few weeks after the record was broken with a four-something megawatt solid oxide electrolyzer system in California in NASA? Bloom Energy. Also we discussed a few minutes ago, Bloom Energy has increased its capacity. Also here in Europe we have Topsoe, for example. Topsoe's core business is about high temperature electrolyzer systems and they are right now finishing one of the biggest manufacturing capacity installations in Europe with 500 megawatts and expectations to be up to a few gigawatts of capacity. Also we have anion exchange membrane. Anion exchange membrane technology is even less mature, we would say, but still we can buy these kind of systems today. Even though they are smaller in size, they are there. Ion exchange membrane, we will not go into detail, but it's kind of hybrid, I always say it's a hybrid between alkaline and PEM.

Just to summarize, there are some challenges as I said that we should look into these kind of systems. We need to reduce the cost of course, and also there are some remaining challenges, for example system efficiency, and for some specific technology also the use of critical raw materials, for example materials that are precious. This is also something to take into consideration. I wanted also to highlight that tracking the evolution of electrolyzer efficiencies is a bit complicated. Why? Because we want to compare different technologies, each technology is different from the other, and also the application depending on the conditions, the efficiency could be seen in a different way. In any case, more or less alkaline and PEM are quite close in efficiency. If we look into high temperature, for example solid oxide electrolyzers, the efficiency is different because of the core of the technology, because there we have high temperatures, and if we take into account different parameters and boundaries, then of course the efficiency increases. But this is one of the examples because we cannot compare exactly the number in efficiency, we should look more into detail in the technology and the application. Just to finalize, because we want to discuss a lot today and we only have a few minutes or half an hour, I would like to highlight also what we are doing in Aragon Foundation. In the Aragon Foundation, we have a long track record in the testing of alkaline water electrolysis. It's something that is in our DNA. We have been for a lot of years testing stacks always in alkaline water electrolysis. The reason was because at the time when the Aragon Foundation was founded more than 20 years ago, it was the most mature technology at that time. In this way, we have had during all these years the chance to build up two testing facilities. We have one that we call industrial scale, we are able to evaluate stacks under state-of-the-art pressure and temperature at industrial scale, just a few cells of course but at the size of the industrial scale. And also we have a pilot scale test bench enabling operation of up to 60 bars. This is very high. As we will hear maybe today, there are some innovations about going to high pressure electrolyzers, and our testing facility is able to test 60 bars and up to 120 degrees. This kind of unique test bench in the environment to test this kind of stacks. And just to finalize before I start introducing our speakers, in this regard the projects where we are involved so far are two ongoing projects and also we have private projects of course because we have this kind of unique testing facilities. So we have also collaborators that are interested in exploring their technologies or to explore the evaluation of their key innovations. Right now I'm coordinating one European project called Hyperell. Hyperell is about trying to advance in the alkaline water electrolysis from the point of view of trying to develop high pressure systems or stacks. So the idea is to see where is the limit for this. We are leading the testing of the stacks at pilot scale. Also we are involved in another project called Endur, also about alkaline water electrolysis, trying to prove the stack with state-of-the-art conditions but try to test with innovative equipment at stack level. For the first time we will evaluate from very specific equipment called ACE, this is about trying to do impedance spectroscopy, very technical, but you should know that this is kind of special and very innovative equipment that we can do not only at cell level as until today in the lab, but also at stack level. From them we can get very useful information in the relevant environment: how is the behavior of each cell inside the stack, and maybe even try to provide feedback to the stack designers or to the stack manufacturers about how to improve even more the stack.

So now we will start with our speakers. I will introduce first An Murray. An Murray is coming from Accelera by Cummins. She works in the electrolyzer division and she's Customer Solutions Engineering Director. Miss Murray has over 25 years of managing complex NPI projects. She started her journey in hydrogen in 2012 by joining Hydrogenics, now part of Accelera. She was responsible for managing several programs in both mobility fuel cells and stationary hydrogen generation applications. In this role, she oversaw multiple world-first breakthrough projects. This includes for example the design and delivery of custom fuel cell engines for the world's first commuter trains in Germany and a large scale power-to-gas plant in Ontario, first of a kind in North America and one of the largest in the world at that time. She then led the design and delivery of the Hylyzer 1000 product, first installed in a water electrolysis plant in Quebec, and it came online in 2020 and was the world's largest PEM plant in operation at that time. She was subsequently responsible for developing next generation PEM water electrolyzer products, and in 2023, quite recently, decided to step back into her customer-facing project execution roots by taking one of these director roles. So please, An, you want to join me? And also I will introduce our next speaker, and then the idea is that they will give a few slides introduction of Accelera and also Nordex, and then we will continue the discussion. So Javier is a mechanical industrial engineer from Navarra University. His work experience began circa 30 years ago in the engine block foundry for the automotive sector where he performed engineering, quality and manufacturing functions, becoming deputy to the head of one of the production sectors. In 2000 he started his journey in the renewable sector in the turbine engineering department, becoming head of industrialization and product support. Then in 2019 he became head of operations and maintenance of the division of Nordex. And in 2022 he changed to the position which he currently holds as Technical Manager for the development of an electrolyzer within Nordex electrolyzer technology. So please, Javier, we will just start with the slides.

Yes. Okay. So very quickly I'm going to run through a handful of slides to introduce Accelera by Cummins. Accelera is the zero emissions branch of Cummins, which has historically been known more for its diesel products, diesel engines and power gen sets. So the Accelera division comprises the zero emissions mobility as well as the electrolysis part, which is the business unit that I'm a part of. You can see here that Accelera and Cummins are well represented globally. We have a footprint all across the world and we have been doing industrial development and technology deliverables for over 100 years as a business. So we're bringing that DNA of quality, consistency and manufacturing scalability into the electrolyzer business. In terms of the electrolysis business, we have the world's largest PEM stack proven in industrial applications. We have been working with this PEM stack for about a decade now in this form factor. The current generation has about two and a half to three megawatts of installed capacity per stack. The Hylyzer 1000 that was mentioned during the intro comprises two stacks to deliver 1,000 normal meters cube per hour in a single integrated unit. We have also a smaller platform called the Hylyzer 500 where we can deliver a turnkey solution for applications where you're looking for 200 to 500 normal meters cube per hour. In terms of some of the projects where we've been using this technology, it's been in industrial scale applications for almost a decade now. Some of them are projects I've had the pleasure to work on. The H2 Linking Core was the first project that used the Hylyzer 1000, came online in 2020. I had the pleasure of leading that project team, it was a fantastic project. The India project beside it, I also had the privilege of visiting that site last year. Mallorca is here in Spain, some of my team members were there just a few weeks ago. And the NextEra project in Florida, we broke our own record and we'll be breaking a record again in a few months. So stay tuned. In terms of the largest PEM electrolysis plants today, the Florida Power and Light project is the largest in operation. But that'll be changing shortly, and then again next year we'll be breaking our record again when the 100 megawatt plant in Germany comes online. That project is currently in manufacturing in our facility here in Spain in Guadalajara. So if any of you have had the ability to visit that site, that's the project we're building today. In terms of summarizing, I just want to say that while Accelera is a very new brand, it's only two years old as a brand, the DNA in electrolysis is very deep. Our business has been working in this industry for over seven decades now, working with everything from atmospheric alkaline, pressurized alkaline, and today pressurized PEM. I've had the pleasure of working with those technologies in my career. We've got a very large install base in industrial applications today in PEM. As was said, this is not in development, this is ready available technology. And also Accelera as a brand is part of Cummins, and Cummins is of course known for innovation and reliability, so we want to make sure that that brand promise stays true in the electrolysis business as well. Thank you.

Thank you, An. Now Javier, please.

Well, Nordex Electrolyzer is a spin-off from Nordex. Nordex is one of the bigger wind turbine manufacturers in the world. So the spin-off was created in 2022. It's 80-85% belongs to Nordex Group and 15% belongs to Sodena, that is the Navarra government society for development. It was the second largest investment in Navarra in a new industry. Our target is to, well, we started analyzing the hydrogen business five years ago in order to look for hydrogen as an energy vector for increasing our core business, which is wind turbines. So we decided to analyze the market and we started seeing that there are many electrolyzer manufacturers but with not enough strength for supporting big projects in remote locations. Our target was really to go for remote locations with high potential in wind mainly, like south of Chile or whatever, and combine wind, solar and electrolyzer. So at the end we decided to go for our own development based on the strengths that the Nordex Group has developed during more than 35 years in the wind industry. We chose the alkaline technology because on those big projects we consider that there are some advantages for the alkaline technology and there are some disadvantages for example with PEM, but that could in some way be reduced using a huge power plant like the flexibility or other things. Our product portfolio is going to be based on a 2.5 megawatt stack also as a base, and later from this base stack develop different modules. In the coming two years we will be developing the 5 and the 10 megawatt modules. But basically we understand that we need to take advantage of scale economy in order to reduce cost. So we are going to develop a base product but later combining those stacks develop modules for bigger power plants. The roadmap, obviously we don't have as much experience as Cummins. We built a first electrolyzer with 50 kilowatts. A second prototype was built and commissioned last year with 500 kilowatts. We are proud of this prototype because we consider it like the first electrolyzer developed, manufactured and commissioned in Spain for that time. This year we are going to commission in summer probably the 2.5 megawatt electrolyzer, and next year we will be developing the different modules with the objective of those big power plants. Regarding timeline, on the upper line you can see what I explained in the previous slide, but in the lower line you can see our intentions for the manufacturing capacities. So we are taking right now for the prototypes and for the pre-serial we are taking advantage of the workshop that we have in the wind industry. So taking advantage of those experienced people assembling, cabling and so on, we are going to start with kind of manual assembly, reaching 100 megawatts we consider that in one workshop we can build 100 megawatts there in a couple of years. And in 2027-2028 we will be building a kind of automatic plant in order to cover the needs of those projects in remote locations that are being developed right now. Nothing else from Nordex in five minutes. Thank you.

Thank you very much to both of you. And now we will start with the discussion. So we have here, as we said, one representative from the alkaline technology and the other one from the PEM. Both technologies are different but of course I assume and I believe also that there are some complementarities between the two of them. From your point of view, which are the main characteristics, technical please, contributing to such synergies? So please, who wants to start? So please.

Well, I guess I can start. Like I said, I've worked with both alkaline and PEM technologies. I do think the obvious advantage that alkaline has is of course in terms of the cost per stack is lower. Although I do question at the total installed cost level, we see that PEM does have a lot of advantages because of the scaling and the size and the highly integrated nature of the equipment. The other advantage from a PEM technology perspective is it has very low turndown, it has very high efficiency, and that roadmap is going to continue to improve that. It also has really good flexibility in terms of rapid response time to change in energy input levels. So today's applications are mostly PPA direct coupled to grid, so the flexibility isn't as critical, but as we move forward in time and we're direct coupling to renewables, wind or solar, the flexibility is going to become a more important aspect of the overall project feasibilities. And then because of the flexibility, there's a very wide range of operating from low turndown to higher current densities, which can help overall reduce the amount of stacks you actually have to install to match your energy profiles. So yeah.

Yeah. It's true that for example the PEM technology has more flexibility. So if you want to connect one electrolyzer with one turbine, obviously the PEM technology is better because you are going to take advantage of most of the power curve from the turbine. But it's true also, as An has mentioned, that we decided to go for alkaline for two main reasons. One was the cost, as An mentioned, and it was not only a question of cost. It was also a question of not having material that could limit your growth, let's say, because at the end the use of PGM materials obviously is more or less restricted to some quantity, and if the market is going to grow as it was expected, probably right now it's more stagnant, but if the market is going to grow, probably you could have some problems with the material. And it's not only a question of cost. And the other one is the durability. It's true that probably PEM is having more efficiency in some cases, but in those kind of big projects in remote locations, if you can work with the same stack for a couple of years more, it makes a huge difference on the OPEX, let's say. So we decided for those two reasons, but it's true that right now the people that are developing those big projects are...

Analyzing if a combination from, let's say, you put more power than the electrolyzer on those big projects. So it's true that probably the alkaline could make the base of the consumption and the production, but later if you have PEM technology inside the same project, you can react quicker to the fluctuation and you can go with less time with flexibility and so on. So I think that could be complementary, but in big projects.

Yeah. So this was my question right in the beginning. Even though there are some differences between the two technologies, this is what it became like an added value, this complementarity for real projects, real projects that we have a real challenge to solve and to find a good solution. Always the best solution is a combination of different options, and as you said, alkaline and PEM would be quite good for this. Regarding you said something about efficiency, durability, lifetime, I would like to go into detail here. So the improvement of the electrolyzer efficiency from the point of view of the stack, but also the balance of plant, is one of the key aspects, of course, because we want to improve the energy efficiency to reduce the cost at the end and so on. So from your point of view or your perspective, which is the level of efficiency that today Nordex and Accelera technologies possess, and which could be the efficiency limit if this is something that you can share, of course, in five years' time, or where is the path where we go in terms of efficiency? But also I would like to discuss in terms of lifetime, because both of them are kind of related. So please, Javier, for example, this time.