Hydrogen infrastructure
Infrastructure is a sweeping term that, for one, encompasses all facilities required to get people, goods, liquids, and utilities like gas and electricity from one place to another. To be able to provide a reliable supply of hydrogen, supply and demand must be properly coordinated, both in terms of time and place. The hydrogen infrastructure is an essential link in this.
It is precisely because of its strong infrastructure that the Netherlands is well equipped to take a leading role in the field of hydrogen. The potential demand for hydrogen in the industrial sector is high, and there is already a nationwide gas infrastructure.
In this section we consider how you can transport hydrogen – in what form and with which means of transport. The choices you make in this area depend on the amount of hydrogen you want to transport, the purpose, the destination and when the hydrogen is needed. The illustration below shows the various options for transport and storage.
Options for hydrogen transport and storage
It is likely that in the future larger volumes of carbon-neutral hydrogen will need to be transported. You can read about this in the linked supply and demand analysis. This can be done, for example, using a national pipeline grid, through pipelines leading directly from providers to requesting parties, and from new storage facilities yet to be developed. Since storage is also a part of the grid, we also handle hydrogen storage in this section.
What’s the smart way to transport hydrogen?
There are various methods for transporting hydrogen from the production plant to the site of the end user. The most cost-efficient, and therefore smartest, method depends on the volumes to be transported and the distance.
Methods of transporting hydrogen
It is likely that in the future larger volumes of carbon-neutral hydrogen will need to be transported. You can read about this in the linked supply and demand analysis. This can be done, for example, using a national pipeline grid, through pipelines leading directly from providers to requesting parties, and from new storage facilities yet to be developed. Since storage is also a part of the grid, we also handle hydrogen storage in this section.
Transporting small volumes
For small volumes, transport under pressure in cylinders is a logical choice, for example in 50-litre gas cylinders or in cylinder bundles. Or it can be transported in tube trailers, i.e. trailers with stacked long cylinders of compressed hydrogen. Tube trailers can deliver from 0.5 to 1 tonne of compressed hydrogen in one journey.
Transporting large volumes
With larger volumes, pipelines become interesting. At the moment, there are already various hydrogen transport pipelines in the Netherlands. Air Products, a large company in industrial gases, manages a hydrogen pipeline network in the Port of Rotterdam industrial area. The company delivers hydrogen to local industry through some 140km of pipelines. A similar company, Air Liquide, connects the Port of Rotterdam with northern France using its hydrogen pipeline grid. Air Liquide also has around 1000km of pipeline in the German Ruhr area. These hydrogen pipelines have a much smaller diameter than the high-pressure gas pipelines in the Netherlands.
Hydrogen pipeline in Zeeland
Spanning a length of 12 kilometres, the Gasunie pipeline links up chemical companies Dow Chemical and Yara in the Dutch province of Zeeland. Originally used to transmit natural gas, Gasunie recently started using the pipeline to move hydrogen. The hydrogen pipeline between Yara and Dow is a good example of the decision to stop transporting compressed hydrogen by road, but rather transmit it through a pipeline. The hydrogen released as a by-product at Dow is used as a raw material by Yara, meaning it is put to use efficiently, while also saving the considerable energy that would otherwise have been needed to produce and transport the hydrogen. Carbon emissions are also reduced. Companies and government bodies made the first agreements on the pipeline in March 2016 and it was commissioned in late 2018.
Transporting over long distances
Occasionally, hydrogen is produced far from the end user, in the Middle East for example, and this will possibly occur more often in the future. In this case, transport by ship is another option, as it is for liquefied natural gas. Especially with hydrogen transport over long distances, it can be economically attractive to further increase the energy density of the compressed gas. There are two options for this:
- Liquefy hydrogen by cooling it to -253°C. The resulting product is called liquid hydrogen (LH₂). A cubic meter of liquid hydrogen weighs about 70kg. To illustrate, one tube trailer can transport around 3500kg of liquid hydrogen, i.e. seven times as much as when transporting compressed gas.
- Temporarily bind hydrogen physically or chemically to other molecules. These ‘Liquid Organic Hydrogen Carriers’ (LOHC) can transport a relatively large amount of hydrogen per m³. LOHC is transported in specially built ships. The chemicals used, like methanol, formic acid and ammonia, do not need to reach as low a temperature as hydrogen to reach a liquid state. However, when the hydrogen is unloaded from the chemical carrier, a lot of energy is lost, so only industries that use these chemicals will find this form of transport to be an attractive alternative.
What’s the smart alternative?
Which option is the most attractive for which situation comes down to economics. Every conversion step – increasing pressure, liquefaction, conversion to other chemicals – involves losses and costs, meaning the alternatives must be weighed for each situation. Other factors, such as safety, also play a role in the choice of transport. Ammonia, for example, is a toxic substance, and so inland transport by rail has been stopped in the Netherlands.
Towards a national hydrogen grid
At present, industry mainly produces its hydrogen locally from fossil fuels. With the exception of Chemelot located in the far south of the Netherlands, the large industrial clusters are situated on or close to the coast. In the future, large amounts of wind energy will be brought from sea to shore. Infrastructure analyses by TenneT and Gasunie show that a solution must be found for the transport of this energy further inland. Large-scale electrolysis for the production of sustainable hydrogen near the clusters along the coast is an obvious choice; the hydrogen produced will then have to be transported.
Wind farms at sea
The Netherlands plans to have at least 11.5GW of offshore wind capacity in the Dutch energy mix by 2030. The extra capacity will mainly be used close to the shore. Given that the most cost-efficient way to use renewable energy is to have the supply and demand close together, wherever possible the energy should first be supplied to industry along the coast. Not all industrial processes can be ‘electrified’ though, meaning molecules will still be needed for the chemical industry. The various industrial clusters along the coast are therefore suitable starting locations for the production and consumption of carbon-neutral hydrogen.
After 2030, the amount of offshore wind energy will increase even further. In its scenarios, the PBL Netherlands Environmental Assessment Agency foresees a strong growth until 2050. It is therefore important for a cost-efficient electrolyser with a capacity of 1GW to be built by 2030 so that future offshore wind farms can also send hydrogen produced on location ashore. And with this, new offshore wind farm electricity connections costing more than 1 billion euros per gigawatt can be avoided.
When looking at supply and demand, the supply of hydrogen has to get to the right place, but it also has to get there at the right time, on demand. This is possible through storage. At present, from a technical perspective it’s only possible to store large amounts of hydrogen in salt caverns. The north-eastern part of the Netherlands has a very thick layer of salt, and salt caverns are already being used to store natural gas there. To provide all areas with the right amount of hydrogen at the right time, a national hydrogen grid is needed.
Gasunie is working on the hydrogen infrastructure
As the national transmission system operator (TSO), Gasunie wants to speed up the energy transition and the further development of hydrogen. In view of this and using the Climate Agreement as a guideline, Gasunie has offered to bring a dedicated hydrogen grid, based on the existing natural gas grid, into operation by around 2030. This network could have a capacity of approximately 15GW by that time. In order to achieve this goal, Gasunie is developing a number of projects with partners in the Eemshaven, North Sea Canal, Rotterdam, Zeeland and Limburg industrial clusters.
In the development of the hydrogen infrastructure, Gasunie is focusing on industrial clusters. Gasunie can replace the current extensive use of hydrogen from fossil fuels with carbon-neutral hydrogen, which it can supply using the new hydrogen grid. Naturally, in the long term, smaller companies, the transport and mobility sector, and local distribution companies can also connect to this national grid.
Planned implementation
When is this all expected to take place? Up to 2025, the infrastructure for hydrogen will probably be developed in the various regional industrial clusters; this has already been stated in the Hydrogen Manifesto (in Dutch) and the Climate Agreement. Detailed concepts have already been devised for this in the Eemshaven (in Dutch) and Port of Rotterdam industrial areas.
Between 2025 and 2030, Gasunie will possibly bring transmission connections between the five industrial clusters into operation, with slight adjustments to the existing gas grid. This way, Gasunie should in most cases be able to make 10GW or more of transmission capacity for hydrogen available. The different scenarios in the 2050 Infrastructure Outlook, a joint study by TenneT and Gasunie, are based on the assumption that three, six or nine storage caverns will be developed. All this is sufficient to meet the projected demand for sustainable hydrogen, in the longer term as well.
Costs
According to initial estimates, the costs of realising this national hydrogen grid will be around 1.5 billion euros. This amount includes the costs of converting parts of the natural gas network, in particular the compressor stations, and laying some new pipelines. For the sake of comparison, the construction of a new national hydrogen grid with completely new pipelines would cost around 4 to 5 billion euros.
This means that by around 2030 we can have a unique energy infrastructure in the Netherlands comprising the electricity grid, a natural gas grid that is partly filled with green gas, and a hydrogen grid as a connecting link. These are networks that reinforce each other and together ensure a reliable, affordable and sustainable supply of energy.
Can hydrogen be used in our natural gas grid?
We have already gained a lot of experience with hydrogen: it’s been used for decades already, in the chemical industry and elsewhere too. Hydrogen is similar to methane, but there are also differences between them. Hydrogen molecules are smaller than methane molecules, and the energy required to ignite hydrogen is substantially less. You have to take these factors into account when transmitting hydrogen using the gas grid and when carrying out maintenance on the network. These differences are still not enough to make the transmission of hydrogen using the gas grid impossible though.
High and medium-pressure network
After extensive research commissioned by the Ministry of Economic Affairs, Gasunie, in collaboration with technical consultancy firm DNV GL, concluded that the Dutch gas grid offers good possibilities for the transmission of pure hydrogen.
Three points from the study require special attention from Gasunie, as explained below.
Integrity
A relatively constant pressure is needed to prevent defect growth through the use of hydrogen, which is why Gasunie will have to monitor the operational conditions to avoid pressure changes.
The integrity of steel
Hydrogen atoms in steel can cause a decrease of the integrity of the steel. The comprehensive name of this decrease is called hydrogen embrittlement. Hydrogen embrittlement takes many forms depending on various factors, including the concentration of hydrogen atoms in the steel. The petrochemical industry has for example hydrogen-induced cracking and the welding world cold-cracks. In those forms the hydrogen concentration in steel is very much higher and cannot be compared with the concentration with hydrogen gas. Therefore these forms of hydrogen embrittlement do not occur in a steel pipe with hydrogen gas.
Hydrogen gas consists of hydrogen molecules. These molecules cannot be absorbed in the steel. Hydrogen can only be absorped as an atom in steel. This is only possible with a clean steel surface. Normally the surface of steel pipes and valves is provided with an oxide layer. Only under certain circumstances such as welding defects in combination with a varying pressure load a clean steel surface can be created. On this clean surface, hydrogen molecules can be decomposed into hydrogen atoms and incorporated into the steel. Once included in the steel, the welding defects can grow faster than with methane. This aspect must be calculated and tested. A restriction in pressure variations can follow from this. Some oxygen (less than 0.5%) in the hydrogen gas restores the oxide layer on the steel so that no hydrogen atoms can be absorbed into the steel.
Compressor stations
The existing compressors are not immediately suitable for handling pure hydrogen, meaning the compressor stations will have to be modified or replaced.
External safety
External safety is not significantly affected when using hydrogen. The energy content (emissivity) decreases and the ignition probability increases. But under the regulations, hydrogen falls into a different category to natural gas and stricter rules apply. Introducing hydrogen could present problems under current regulations, while the safety problems seem manageable.
Low pressure networks
That converting a Gasunie pipeline is feasible in practice has been proven in the Zeelandic-Flanders region of the Netherlands, where Gasunie has repurposed an existing natural gas pipeline for use in distributing hydrogen. A comprehensive safety study showed that the pipeline is suitable for the transmission of hydrogen. Gasunie is also using this pipeline to gain experience with hydrogen transmission. You can read more about this in the article on the right (in Dutch).
Why do Dutch gas transport companies not (yet) feed hydrogen into the natural gas grid?
In the Netherlands, local gas transmission and distribution networks may contain on a small percentage of hydrogen. These strict laws and regulations are in place primarily to protect the consumer: it is mainly the burners in people’s homes and in industries that cannot handle high percentages of hydrogen.
A higher percentage of hydrogen in the gas grid will likely be allowed in the coming years. Maybe on a national scale, but also possibly during tests on a local or regional scale. Before this can be done, however, the Dutch government will have to amend the legal framework.
Thanks to its extensive natural gas infrastructure, the Netherlands has the possibility of bringing into operation a dedicated hydrogen grid in addition to the existing gas grid. The demand for natural gas and domestic production is declining and various export contracts are coming to an end. This puts the Netherlands in the unique position of being able to repurpose part of the gas grid for the transmission of hydrogen. As such, we can make optimum use of the supply of hydrogen and we can prevent energy losses.
Storage in salt caverns
The way we store hydrogen is often directly linked to the way we transport and use it. If you want to move large quantities of hydrogen, this is best done through pipelines. Pipelines are not really suitable as a storage facility however. In the Netherlands, we can use salt caverns and possibly also depleted gas fields for large-scale storage. But there are also other alternatives. Liquid hydrogen is often transported by ship. A good example of large-scale storage of liquid hydrogen is the facility at the base in Cape Canaveral, Florida (USA), which has a storage capacity of 3800m3 (270 tonnes). Chemical storage by binding hydrogen with ammonia, for example, is another option.
Depleted gas fields offer the largest capacity for the storage of hydrogen, but before we get that far a lot of research is needed. We need to find out, for example, how the hydrogen will react with the remaining methane and the bacteria in the reservoir, and whether the cap rock is sufficiently impermeable (i.e. gas-tight). Energie Beheer Nederland (EBN) and the Netherlands Organisation for Applied Scientific Research TNO have conducted an exploratory study into the storage of hydrogen in depleted gas fields, as well as into other forms of underground storage such as caverns.
Though a salt cavern has less storage capacity than a depleted gas field, it offers major advantages. The hydrogen molecules cannot escape through the salt layer of the salt caverns, and there’s no residual methane or other molecules or bacteria for the hydrogen to interact with. The storage of hydrogen in salt caverns is already commonplace in the US and the UK.
The first analyses based on the Grid of the Future (in Dutch) scenarios of Netbeheer Nederland (association of Dutch energy distribution companies), and the supply-demand analysis of the cross-sectoral study group on hydrogen show that, by 2030, three to nine salt caverns will be needed to provide the required flexibility in the hydrogen supply system.
Storage in salt caverns
The storage capacity of a salt cavern is approximately one million cubic metres, good for storing 6100 tonnes of hydrogen, which in turn corresponds to 240,000 MWh (almost 1 PJ). To give you a comparison, a Tesla Powerwall has a storage capacity of 10kWh, so one cavern has as much storage capacity as about 24,000,000 Powerwalls. Even if we take the largest battery in the world, the 129MWh Hornsdale Power Reserve built by Tesla in Australia, we would still need 2000 of these to provide the same storage capacity.
Comparison of the storage capacity for natural gas, hydrogen and electricity
- Metres refers to an indication of the length of the installation (Google maps analysis)
- The costs are a broad estimate of the expected costs per KWh storage capacity (based on www.deltalinqs.nl/stream/h-vision-eindrapport-blue-hydrogen-as-accelerator)
- The information about Jamestown was taken from www.abc.net.au/news/2018-09-27/tesla-battery-cost-revealed-two-years-after-blackout/1031068.
The geological conditions in the north-eastern part of the Netherlands are right for leaching out salt caverns. We have been using this sort of cavern for about ten years already to store natural gas. We are now on the eve of hydrogen storage.
One of the projects in which Gasunie is closely involved is the HyStock pilot project, which includes an in-depth study into all the aspects of storing hydrogen in salt caverns with the aim of developing the first of these hydrogen caverns.
The Gasunie HyStock project, in which conversion, transport and storage of hydrogen come together in one location (click the image to enlarge).
