New Energies, new possibilities

Demonstration system for carbon-free generation of electricity with ammonia in high-temperature fuel cells (SOFCs)

Using hydrogen to generate electricity does not cause any climate-damaging emissions. But storing and transporting the gas pose technical challenges. With this in mind, Fraunhofer researchers use ammonia, a hydrogen derivative that is easier to handle, as a starting material. Ammonia is cracked in a high-temperature fuel cell stack, and the hydrogen produced in this process is converted to electricity. The waste heat can be used as heat energy, for example.

There are high hopes for hydrogen and its derivatives as sources of energy. They play a central role in the energy transition component of the German federal government’s National Hydrogen Strategy. Ammonia (NH3) has been identified as having especially high potential, as hydrogen is easier to store and transport in the form of ammonia. A team of researchers with Prof. Laura Nousch from the Fraunhofer Institute for Ceramic Technologies and Systems IKTS in Dresden has developed a demonstrator based on a high-temperature fuel cell stack (solid oxide fuel cell, SOFC) that can use ammonia to generate electricity directly and with high efficiency. Electricity and heat are generated in a single compact system — without CO2 emissions or other harmful byproducts.

© Fraunhofer IKTS--Schematic of the principle behind an ammonia SOFC system

Ammonia becomes hydrogen, hydrogen becomes electricity

Fraunhofer researcher Laura Nousch explains the advantages of this method: “Ammonia has been used in the chemical industry for decades, for example to produce fertilizers, so there are established and familiar processes of handling this substance. However, it still needs to be treated with caution. As a hydrogen carrier, ammonia offers high energy density, and at the same time it is relatively easy to store and transport. Ammonia is an ideal starting material for climate-friendly generation of electricity and heat energy.” In the process, ammonia is first conditioned and fed into the cracker, where it is heated to temperatures of 300 degrees Celsius or higher. In response, it breaks down into hydrogen (H2) and nitrogen (N2). When the process is completed, the nitrogen can simply be released together with water vapor as harmless exhaust gases. Then, the hydrogen is fed into the high-temperature fuel cell. In the ceramic electrolyte, it flows over the anode, while air streams pass the cathode. Splitting the hydrogen releases electrons that move from the anode to the cathode. This is how electricity starts to flow. In addition to water vapor, this electrochemical reaction also produces thermal energy. The afterburning also generates heat. “The heat is used to maintain the high temperature inside the cracker and is also released as waste heat. The latter can then be used for purposes

High efficiency by 60 percent

When designing the system, the researchers at Fraunhofer IKTS drew on their decades of expertise in working with ceramic fuel cell stacks. The team was able to build a fuel cell demonstrator that handles the entire process of breaking ammonia down into hydrogen and subsequently generating electricity from it all in one device. The efficiency of this method, just like those based on natural gas, stands at 60 percent, but with the difference that ammonia SOFC systems are comparatively simple and robust in structure. The system is perfect for smaller industrial companies that want to generate electricity without carbon emissions but are not connected to the future core hydrogen network, or for municipalities and local utility companies looking to supply green heat to their customers. Even large ships can be equipped with ecofriendly drives based on ammonia/hydrogen in this way.

Customized fuel cell systems

The higher the temperature in the cracker, the more of the ammonia is broken down into hydrogen. In turn, at lower temperatures, meaning just over 400 degrees Celsius, a considerable portion of the ammonia remains. “However, our tests showed that the ammonia molecules also break down completely into hydrogen in the high-temperature fuel cell. This can even increase the system’s overall performance,” Nousch says. And that opens up various options for thermal management. “Targeted design and smart thermal management are combined with other modifications to aspects such as the power and the size of the fuel cell stacks. So, we are able to devise customized solutions for climate-friendly generation of electricity and heat, especially for small and medium-sized enterprises,” she explains.

Fraunhofer's NH3 System Hydrogen Technology: Unlocking Climate-Friendly Electricity

New offshore wind farms are going to generate a lot of sustainable electricity in the future. Some of that electricity will be converted to hydrogen and brought ashore through pipelines. But why is that, and how exactly will it work? And what role does Gasunie play in this? Seven questions and answers about the offshore hydrogen network.

1. Why is there a need for offshore hydrogen?

In the Dutch Climate Agreement, it has been agreed that the Dutch energy system will be made more sustainable. Implementing sustainability measures will help us cut carbon emissions and mitigate climate change. Wind energy is a good way to do this, but it requires a lot of space, which is why we are building wind farms offshore.

The electricity produced by these wind farms is brought ashore through power cables. However, this is becoming increasingly difficult. It is costly, the power cables require a lot of space and the power grid has limited capacity. What’s more, we need a solution that provides power when the sun is not shining and the wind is not blowing. This is where hydrogen plays an important role; it is a form of energy that can easily be stored and transported.

So hydrogen will soon be generated offshore using wind energy and then brought to land via (existing) pipelines. This is cheaper than laying power cables and opens up the possibility of storing energy in the form of hydrogen.

The Dutch government has set upper targets for offshore wind capacity of about 21 gigawatts (GW) up to 2030, 50GW by 2040, and 70GW by 2050. To put that in perspective, an average power station has a capacity of 1 GW.

2. How and where is the hydrogen produced?

Hydrogen is a gas that we can use as an energy carrier. This allows us to transport or store energy. Hydrogen is generated by passing an electric current through water. This process is called electrolysis and it can be done either on land or offshore. In an offshore scenario, we can use the power generated by offshore wind turbines for this purpose. This is how we produce hydrogen without carbon emissions. We call this ‘green hydrogen’.

Research and test environments will clarify how we can best apply electrolysis at sea, either in the individual turbines, or at a central location. We will then transport this green hydrogen via pipelines to land, into the future Dutch national hydrogen transmission network (Waterstofnetwerk Nederland).

3. What is Gasunie’s role in relation to offshore hydrogen?

Gasunie has been designated as the transmission system operator for the future hydrogen network in the North Sea. This was announced in June 2024 by Rob Jetten, who was at the time the Dutch Minister for Climate and Energy Policy, in a letter to the Dutch House of Representatives. In a letter on the North Sea Energy Infrastructure Plan 2050, Jetten stressed that this is important for safeguarding public interests. Additionally, the designation of Gasunie reassures the market that infrastructure will be available. In light of the key role that offshore hydrogen production is expected to play in the future growth of offshore wind, Jetten asked Gasunie to set the wheels in motion towards creating an offshore hydrogen network. This hydrogen network will help achieve Dutch climate goals and energy independence, and improve the Netherlands’ competitive position.

This means that Gasunie will soon be responsible for the transmission of hydrogen produced offshore and the associated infrastructure, just as it is on land.

4. What are Gasunie’s offshore activities?

When we talk about HyOne at Gasunie, we mean the entire hydrogen infrastructure that will soon (between 2030 and 2050) be in operation in the North Sea. Various projects and programmes are under way to help develop this infrastructure. One programme centres mainly on the undersea pipelines and their landfall points and on the associated installation technology, while other projects focus on the development of new wind power areas. Through these programmes we are helping to shape the energy system in the North Sea while also demonstrating the feasibility of the hydrogen network.

• For example, the power generated offshore needs to be connected to the onshore power infrastructure. Gasunie is a partner in the Eemshaven Offshore Wind Energy Connection Programme (Aansluiting Wind Op Zee-Eemshaven, PAWOZ) and the Investigation into Landfall Options for Offshore Wind Energy (Programma Verbindingen Aanlanding Wind Op Zee, VAWOZ). In these programmes, the Dutch Ministry of Climate Policy and Green Growth is examining options for offshore cable and pipeline routes. These routes run from wind farms in the North Sea to the mainland.
  
  
• In addition, we are actively collaborating in the North Sea Wind Power Hub programme. This programme is investigating how we can generate, collect, connect and convert offshore energy in the future. The programme looks at (1) the use of international power connections, and (2) offshore conversion of electricity into hydrogen (using electrolysis).
• For the further roll-out of offshore wind power, the Dutch government, Gasunie and Dutch electricity TSO TenneT are focusing on creating energy hubs. These hubs are large-scale wind farms where energy is generated, on the one hand in the form of electricity (electrons) and on the other in the form of hydrogen (by converting electricity to hydrogen). Both of these forms of energy are then brought ashore. The energy hubs can also become connection nodes for international connections.
• Because the roll-out of offshore hydrogen is at the development stage, the Minister of Climate Policy and Green Growth has announced that the roll-out will be given a boost through the start-up of two offshore demonstration projects, known as Demo 1 and Demo 2. Demo 1 is an offshore hydrogen production project aiming for a production capacity of up to 50MW. It is expected that hydrogen production will start in late 2030. Demo 2 is the next step along the pathway to the large-scale production of offshore hydrogen. An offshore electrolysis project with a capacity of around 500MW will be constructed at the planned wind farm. The project is scheduled to be operational in 2033.
  Though Gasunie will not play a role in hydrogen production through electrolysis, it is closely involved in both Demo projects as the party developing the infrastructure that will bring the hydrogen to shore.

5. How does Gasunie take into account nature on and in the North Sea?

The North Sea is intensively used for various purposes, including activities and sectors such as fishing, shipping, wind farms and cable and pipeline construction. These activities can have a significant impact on the ecosystem.

At Gasunie, we are designing a network that takes the North Sea’s ecological resilience into account as much as possible. Put simply, this means that we know how much human activity the sea can tolerate before ecological damage occurs and actively control our operations to remain below that level. If we do too much, nature can’t recover, and the underwater flora and fauna will be adversely affected.

So we are exploring the possibility of implementing both conservation and nature-enhancing measures. This is also encouraged by laws and regulations, such as the Dutch Nature Protection Act, the EU Birds Directive and Habitats Directive, the EU’s Common Fisheries Policy and other EU biodiversity strategies and directives. In addition, there is a North Sea Agreement that documents agreements up to 2030 between the state and stakeholders. This is how government agencies and stakeholders work together in shaping the three major transitions on the North Sea: energy, nature and food, and the connection between them.

In other words, it’s important to find a good balance so that we can use the sea without pushing past its limits. This keeps the North Sea healthy and full of life.

6. Why do offshore hydrogen projects and programmes often have long completion times?

Long completion times for offshore hydrogen projects are caused by several factors. There’s the complexity of the infrastructure, for example; questions like how and where the pipelines will be installed, what local factors need to be taken into account, and can we reuse existing pipelines? Technological challenges obviously also play a major role in this. Time is needed for research, development and testing: only then can we build a reliable, sustainable, safe infrastructure.

Large-scale hydrogen projects involve hefty investments. Funding and cash flows require close attention and precision. In addition, obtaining permits can take time, especially since offshore hydrogen projects often involve new technologies and methods that are not yet fully covered by laws and regulations.

The local communities also need to be actively involved in projects of this nature. Gathering the right information and establishing lines of communication also takes time. Finally, in offshore hydrogen projects, we work closely with different parties, including government agencies, companies and research institutions. Effective collaboration is key here, and coordination between all those parties can be complex and time-consuming.

7. What influence do stakeholders have and how are they involved?

We refer to individuals and organisations that need to be involved in our projects or programmes as ‘stakeholders’. They are closely involved in the different hydrogen programmes. Stakeholders not only include local residents, but also nature and environmental organisations, fishing and shipping businesses, civil society organisations, government departments, and many others.

The Investigation into Landfall Options for Offshore Wind Energy programme (VAWOZ) is a concrete example. The central question here is how and along which routes the energy from the planned offshore wind farms can best be brought ashore. In spring 2024, the draft VAWOZ investigation plan was available for review. After publication, anyone who wanted to could respond. There were 2,273 responses in total. This was valuable, as a number of responses led to modifications to the final investigation plan. The completion of this plan is seen as an important milestone in the programme. Gasunie, together with the Dutch Ministry of Climate Policy and Green Growth, TenneT, Rijkswaterstaat and provincial authorities, also sees this approach as a valuable participation tool for all stakeholders.

The programmes also organise multiple meetings for stakeholders, not only to keep them informed, but also to solicit input on potentially suitable routes and locations for bringing the cables and pipelines ashore. This approach allows us to access their knowledge and gives us a good picture of the various interests. This is how we arrive at the best solutions in each case, which are also supported by many stakeholders.

Offshore Hydrogen: 7 Questions and Answers