Podcast-Transkript – zur Audio-Version gelangen Sie hier

H₂News: Welcome to the third H2 on Air special episode! My name is Magnus Schwarz and I’m excited to have two distinguished guests with me today: Doug Waters and Jörg Lennertz from Uniper. We’ll be exploring the critical role of renewable energies for this Düsseldorf-based company, diving into why energy storage is absolutely essential, and uncovering how hydrogen is set to become a game changer in this area. Let’s kick off by getting to know our experts. Doug, tell us about your role at Uniper and what drives your work there.

Doug Waters: So I am Doug Waters and I am responsible for all of Uniper’s energy storage activities. That’s about 80 TWh of natural gas storage in Germany, the UK and Austria. We’re also investigating the storage of green gases in all different forms and at different types of storage mediums. And in addition, we also look after the caverns for Uniper Kraftwerke, the power station company, storing compressed air in northern Germany as well.

H₂News: Excellent. Now Jörg, you’re heading Uniper Renewables as the CEO. Tell us something about your agenda there and what your work focuses on.

Jörg Lennertz: Yes, happy to Magnus. I’m heading the Renewables Business Development unit in Uniper. So, we are developing onshore wind, solar PV and Co-located BESS assets across Europe. We are currently an organisation of a bit more than 200 people. We have built up the business over the last around four years, so both in terms of people but also pipeline. We are very glad to already today look at more than 3 gigawatts of projects in advanced development. And within Uniper, we are also at a very interesting point in time after building up the business over the last years to also go into execution of assets. So, we have our first onshore wind and solar PV projects in construction, and we are preparing many more to also go into execution still this year.

H₂News: Thank you, Jörg. That’s an impressive scale. Now the energy transition is dominating conversations everywhere – from boardrooms to policy circles to media headlines. And for both of you, this isn’t just industry buzz; it’s your daily reality. Jörg, help us understand how Uniper is actually driving this transformation forward.

Jörg Lennertz: I mean, obviously the energy transition as such is a wide challenge, and that’s why I think it was wise we chose to have Doug and me now in parallel here in this interview – Doug representing the molecule side of things and me maybe more the electrons. And I think that’s very symptomatic for Uniper because Uniper, with its more than 100 years of history and its very wide business portfolio, I think is uniquely positioned to run the energy transformation. So, when we think about that, I think that goes well hand in hand, also across technologies and businesses – not only onshore wind, solar PV and BESS, but different molecules and infrastructure storage and so on.

H₂News: That’s really interesting – this idea of bringing together the molecular and electron sides of energy. You mentioned that the integration challenge is where Uniper’s experience really comes into play. So practically speaking, what does this look like in terms of scale? Where does Uniper stand today with renewables and where are you heading?

Jörg Lennertz: Uniper did decide after its spin-off from E.ON to also build up its own renewables platform, not simply because Uniper wanted to be a late joiner to the party in an already very mature and competitive industry, but given Uniper’s unique position of bringing together the different businesses that matter, I think, in the more complex energy future. The technology – onshore wind, solar PV in particular – luckily has become more proven and less of a challenge, but the integration of new renewable generation capacities into the energy system and also the management of, for example, merchant power risks and the optimization of it – that becomes more, I think, the decisive factor, which exactly plays into Uniper’s history and capabilities not talking strictly about the power market in itself alone.

With that in mind, we did build up the business over the last four years, and we have the strategic target to realize 10 gigawatts ready-to-built capacity of renewables in the early 2030s.

Our strategy to do so is not at all limited by the capital available that Uniper Group will provide in investing into our developed onshore wind and solar PV assets. But we are very flexible also in commercializing those – like develop, build and sell together with develop, build and own. That’s our approach to remain flexible there, which also gives us the freedom and the flexibility to do as much renewables as we can for our own company or for third-party investors.

H₂News: OK, thank you. You’re definitely planning on a gigawatt scale . Before we dive into the complexities of energy storage, I’d love to get a sense of what your renewable agenda looks like in practice. So you’ve got an impressive portfolio across seven countries. Could you give us the insights on some of the standout projects? What are your favorite projects?

Jörg Lennertz: As I said at the beginning, after we have been building up the pipeline and the teams currently in seven countries – so up in Sweden, but also in the UK including Republic of Ireland, Poland, France, Italy, and Hungary and Germany, we currently have what I think is quite a representative set of projects in construction, and they are all very unique and very different, as our project pipeline is.

There is maybe the smallest project, which is in Wilhelmshaven, which is a solar PV project which is pretty unique given that it’s constructed on a former landfill – like a fly ash site of our old power plant area in Wilhelmshaven. So that also, if you think about the engineering and construction part of it, makes it quite unique, also the solutions the team did find to build that.

Then we have two solar projects in the UK. They are both also different in terms of energy offtake – like how we market and sell the electricity produced. One project is dedicated for a corporate PPA, the other has secured a CFD. So also there, a good example of the different offtake strategies we are pursuing with our renewable assets. Then also in Scotland, we have a first onshore wind project, also in execution, and we have further solar projects also in execution in Hungary.

And finally, also these projects have also been originated with different strategies.

H₂News: Thank you, Jörg. Now Doug, here’s where the complexity kicks in. Uniper’s building this incredible renewable capacity, but there’s this fundamental challenge: renewable energies are unstable or intermittent by nature. You can’t simply flip a switch when the sun isn’t shining or the wind isn’t blowing. Could you break down what makes renewable energy storage such a complex puzzle, especially from a seasonal perspective?

Waters: So I just like to think about the energy trilemma or the transition, which is about decarbonization – which is predominantly with renewable electricity, so electrify as much as you can and use green electricity. You have security of supply, which means for example, you have a lot more renewable electricity at certain times of year and other times of year, or at certain times of the month, etc. So how do you move energy from one time period to another to ensure security of supply?

You have the geopolitical element to security of supply – so how do you make sure you diversify your supply of that energy? And then you have the cost to the customer – and how do you make sure the cost of it is as low as possible? And the role of storage in all its forms – from battery all the way through to large-scale molecular storage – is to try and find the right balance in this trilemma, between those three, sometimes competing, forms.

In the current world, we do that with methane storage because methane is used for domestic heat in many people’s houses. In the future, that’s probably electrification using a lot more electricity in the winter than in the summer, and then you have certain industries that require methane – maybe some of them will move to electrification, some of them will move to hydrogen, and then you have certain chemical processes, for example, that require certain feedstocks like methane, hydrogen, etc. You need to decarbonize all of those things at the same time, paying attention to security of supply and the end cost. And so, the role of us as a storage operator is to provide that balance, and that’s what we’re investigating – what type of technologies can we use, what type of molecules can we store that enable that transition to happen in the most cost-effective and secure way.

H₂News: Thank you, Doug. That trilemma approach you mentioned really captures this complexity perfectly. Today’s storage challenge is largely solved by methane, as you said – so natural gas storage. Could you give us a short overview of Uniper’s current storage capabilities or facilities and where they are located?

Doug Waters: We have two different types of methane storage – this depends on geology. So, in the south of Germany and Austria, you have so-called porous rock storages with aquifers or former gas fields where we still use that geological structure to inject the gas and then produce it again in the winter. That’s generally very large capacity and more seasonal in their nature, so you fill them up in the summer and empty them up in the winter. And that’s about half of our capacity which is mainly in southern Germany and Austria.

And then in the north of Germany and the UK, we use salt structures that we make caverns in the geology in the salt domes. And again, that’s about 50% of our capacity, and that’s generally much faster, so you can inject and withdraw not on a seasonal timescale but on weeks or months. So you can use it much more flexibly, but that’s generally less big than the porous rock stores.

So that’s how we do methane storage at the moment. Obviously, we have other ways of storing energy – for us, that’s compressed air. That’s kind of like pumped storage hydro where you don’t have mountains, so instead of pushing water up a hill and letting it down, you put air into a cavern and then let it out at different times of the day. And of course, we have batteries for more short-term storage. So that’s where we are today.

H₂News: Interesting. So, you’ve got different storage technologies and you’re matching them with specific use cases. Now let’s talk about another way of storing energy, and that’s seeing a tremendous amount of hype: hydrogen. Hydrogen has been discussed as the silver bullet for renewable energy storage. Could you tell us something about how it can be stored and how you have been testing hydrogen storage at Uniper?

Waters: We need to look at what role hydrogen has in the energy transition, and I think that will depend on the economics and the regulation. Hydrogen will be required in some key industries that are currently using fossil hydrogen. So I can see the need to store hydrogen at very large volume, which is very different to storing methane at very large volume. You have lots of technical challenges in storing hydrogen which are different to storing methane. But what we have been able to prove in our pilot projects is, you can overcome all of these – it’s just a matter of making sure your process safety, the materials, and the thermodynamics are all covered in the way you handle that storage of hydrogen. So we’ve done a lot of work on doing that, both in salt and in porous rocks – both types of storage I mentioned before. And now we wait to see how the market wants to develop.

I think my key challenge there is to build the storage site – it takes between five and ten years, so it’s not like someone can decide on Monday that they want to do it and then need it on Friday. So we need to have some long-term planning and strategy in that process.

H₂News: So that brings us to the technical reality of scaling hydrogen storage. You’re pioneering this technology, but I understand you can’t simply switch from methane to hydrogen storage overnight. What are the key technical challenges you’re tackling?

Waters: Yes, so the first challenge with hydrogen is it’s a very small molecule. Whereas you might have a steel pipe where natural gas can’t come out of, the hydrogen molecules can get into the material – so that’s a process called embrittlement, and that affects your materials choices very differently to natural gas. So that’s been a lot of work we’ve been doing with a number of technical universities in Germany to try to understand which materials work better at storage pressures of 200 bar or very high pressure. So that’s been – that’s one of the first key building blocks, is ensuring the integrity of the materials. So that’s a big: yes we can and we understand what to do.

The second challenge of hydrogen is it’s a lot less energy-dense than methane. So to store the same amount of energy at the same pressure as hydrogen, I need between four to five times the same storage caverns. So if I have one cavern for methane, I would need four to five caverns for hydrogen. So you need to understand how to handle that.
And then hydrogen has some strange behavior when you increase its pressure and so on, which I won’t go into detail about. You just need to understand that it’s not natural gas, for example. When you increase its pressure, natural gas temperature increases, and that’s not the case for hydrogen, for example. So understanding all those things and how to work with it.

Hydrogen is a different molecule – you need to understand all the process safety requirements around that. How you are going to handle it in case of emergencies, etc. We’ve been through a lot of that, so in our pilot cavern in Krummhörn in northern Germany, we’ve been through all the process steps, and we hope to get an operation plan later this year to start testing the injection of hydrogen into the cavern. But it’s not, like I said before, something where you can switch over on a Friday and then stop methane and turn on hydrogen on Monday. It’s definitely not like that, and policymakers need to understand that.

H₂News: Alright, so now we’ve talked a lot about Uniper’s activities in renewables as well as in the energy storage department. You also explained how hydrogen could play a role, Doug, and why there are specific difficulties with storing it. Now let’s get to a more strategic point of view. Jörg, from your renewables perspective, should hydrogen be the primary storage solution for excess renewable energies, or is it more one of many options?

Lennertz: What I find especially fascinating is what Doug mentioned: the wide range of energy storage technologies and solutions that Uniper already operates, drawing on decades of experience, as well as our ongoing efforts in hydrogen to support the energy system transition. And that’s multi-commodity – that’s interplay between green electrons and also different green molecules potentially.

And also projects like in Bad Lauchstädt are a good example where Uniper is fully integrating, starting from green electricity production from wind and then electrolysis and then hydrogen storage, transportation, and of course, very crucial marketing of the product to make this all a viable business. And also there, recently adding solar PV and continuously optimizing also the green electricity supply in the case of hydrogen production and, as Doug said, hydrogen storage and the technical feasibility of it.

I think this is something where Uniper is providing, let’s say, the basis for essentially regulators and the energy market to eventually pick up on. And I think this whole bandwidth of energy storage is needed in the end to allow for a faster and more rapid build-out of renewable electricity anyway. And that’s including hydro, that’s including lithium ion battery storage – that’s all technologies, and that makes also, I think, Uniper so unique to drive energy transition not only from an electrification point of view, but from a point of view to make also the energy system, the integration of new renewable capacities, work.

H₂News: OK, interesting. I feel like we’re getting to a really crucial point here. Hydrogen is not the only solution for storing renewable energy, and it might not even be the best solution, but it will certainly play a role in this great story of the energy transition. So what do you think this role of hydrogen will look like, especially when it comes to energy storage?

Waters: I don’t think the story is yet clear. So we need to electrify as much as possible with green electricity, but that can’t come without challenges – that is sunny in the summer when you don’t need the electricity, and it’s cold in the winter when you’re going to need lots of electricity when everybody has a “Wärmepumpe” at home, right? So that’s a structural challenge. Now how do you deal with that? No one’s clear on that.

There are different storage technologies that work on different ways, from batteries which can manage up to a day, all the way through to storing large quantities of molecules and then burning them and taking the CO2 off, or making sure they’re green molecules, or just accepting that the CO2 goes into the environment. I think no one’s clear on all of that.

And Jörg’s point was key – we can’t wait until we know what the answer is. We need to do as much as we can now and understanding hydrogen storage and how it works technically is to make sure that if someone says “Can we do it?” The answer is „Yes, this is the cost, this is the lead time and we know how we’re going to do it.” Because if we wait for someone to decide what they wanted, it is too late.

And here, the example Jörg gave in Bad Lauchstädt is a really good example where we’re producing hydrogen from green electricity, and that hydrogen is being used to displace fossil hydrogen in an oil refinery, That will always occur. What else can hydrogen been used for. I think it depends on how much hydrogen there is, and what it costs and what the competing technologies are.

At the moment, there’s not enough green hydrogen around, so it’s kind of a chicken and egg problem. When someone works out how to make green hydrogen at a reasonable price, the market will be flooded with it, and then people will want to store it from times when it’s abundant to times when it’s not. But we are not there, yet. So I guess it’s about putting the building blocks in place so everyone is ready if and when that happens.

Jörg, do you have a different view on that?

Lennertz: I think it’s too early to tell, but we will see, and I think we are doing our part to allow for that. But it’s up to policymakers and markets to decide, and I think we as Uniper – not only from energy storage but also from other flexible, clean, dispatchable power solutions – we are there. Also, if you look at our conventional power plant fleet and so on, for us in Uniper Renewables, it’s not a conflict of „why do you do renewables in a company that’s also so active in fossil?“

It’s not a contradiction, but actually every gas-fired power plant today is helping to allow for further electrification to happen, for further renewables build-out to happen, and that with drastically lower carbon emissions overall. Even if you were to keep today’s CCGTs in the market, maybe operating only in hours where needed to intermittent solar and wind generation, that makes a whole lot of sense from a decarbonization energy transition point of view.

Waters: It’s about flexibility and pragmatism and not having religious doctrine of „we must do everything like this.“ And we know that if you do that, you end up in endless discussions for years. We just need to get on and get doing stuff that makes sense today, and let the future be what the future will be. And I think that’s the key priority, and that’s what Uniper’s about.

Lennertz: Nothing to add.

H₂News: OK, thank you both so much. It has been really interesting to listen to both of you, and it’s also refreshing to hear that pragmatic approach because often times this field is very dominated by ideological debates. Now looking ahead, Germany has committed to achieving net zero by 2045, which is an incredibly ambitious timeline considering that we are a largely industrialized country. And based on everything we’ve discussed today, what would be your key recommendations to policymakers to actually make this happen?

Lennertz: In principle, I would argue that speed is of essence. Also on the example of hydrogen – next to technical challenges, it’s mostly about regulation. And the same for the energy transition as a whole, and especially in Germany, we often see the tendency to think through to try to come up with the most perfect solution and framework. And here I would strongly lobby to also look at what is there – maybe also in neighboring countries – talking about capacity markets and other stuff, and always put speed as the priority.

And why is that? Because climate change is happening and it does not wait for policymakers. So every little action that we can make happen that reduces CO2 emissions, that reduces global warming in the next years, will have an impact and will also have economic value compared to doing less and then being confronted with much higher costs of adapting to climate change. So clearly, for all societies and for policymakers, speed should be the highest priority.

Waters: And just to add to what Jörg just said, I think we need to be pragmatic. So don’t find the perfect solution for everything because there probably isn’t one, and accept that in different places, different solutions might work better. So for example, carbon capture might work better where you have offshore oil and gas fields, but hydrogen might play a role in certain industries and certain geographies compared to others.

So it’s not a one-size-fits-all solution, and it’s all about finding this balance between the decarbonization, what Jörg mentioned, how much is it costing and what it means for security of supply. And you need to always find that balance in any of these energy situations. And I think that’s the role that you need from a government – a clear policy framework that is not too prescriptive and allows pragmatic solutions, but at the same time incentivizes choices that line up with that policy framework.

H₂News: So speed and pragmatism – those themes keep coming back. Now as we wrap it up, I want to give you both the final word. We’ve covered an enormous amount of topics today – from Uniper’s ambitious renewable projects to the technical complexities of hydrogen storage. When our listeners think about Uniper’s role in the energy transition, what’s the one key message you want them to take away?

Lennertz: For me, it boils down to Uniper being the one to link the different bits and pieces of the energy transition. And second, as so many people and companies are talking about the energy transition and claiming they’re part of it, I think Uniper certainly is the company who does it. But I think also today is a good example – every now and then we also need to speak about it like to you and your audience today. But Uniper certainly is a company who does the energy transition.

Waters: And I just to build on that I think we are flexible and pragmatic as a company. So we don’t believe in anyone’s solution – we will go and find the right solution for the right use case, and that’s the important thing from my perspective.

H₂News: Alright, I think you so much for these closing thoughts. I think they wrap it up pretty nicely. Doug, Jörg, thank you also for this incredibly insightful conversation. You have given us a masterclass in the realities of energy transition – from the technical complexities to the strategic thinking that is required to make it all work and figure out how all the pieces of this whole energy transition puzzle fit together.

To our listeners, thanks for joining us for this deep dive into the energy transition with or without hydrogen. And until next time, this has been H2 on Air.

Waters: Thank you very much. Cheers.

Lennertz: Bye-bye.