NOGAT en Noordgastransport (NGT) have published a paper on offshore hydrogen transportation through re-used natural gas pipelines in the Dutch part of the North Sea. Using existing pipelines saves cost and can speed-up the roll-out of large-scale green hydrogen production.
The ambitions for wind energy from the North Sea, and for hydrogen production, have recently been raised. By 2050, the goal is to have 70 GW of wind power generated in the Dutch sector of the North Sea. Besides electricity, offshore green hydrogen production will play an important role for locations further from the coast, as indicated in the Parliamentary Letter Offshore Wind Energy 2030-2050 dated September 16th, 2022.
Hydrogen production from wind energy offshore will be cheaper and more efficient than hydrogen production onshore, because several electricity conversion steps can be skipped. In addition, over larger distances hydrogen transport through pipelines is a cheaper and more efficient way to transport energy, when compared to electricity transport through cables.
Also read: Next step for Scottish floating-wind-to-hydrogen demonstrator project
Existing pipelines
In the Dutch North Sea, there are a number of large pipelines (36-inch diameter) that are suitable and can be re-used for hydrogen transport. These pipelines are conveniently located in relation to the wind (search) areas and are already connected to gas fields that could potentially be re-used for large-scale hydrogen storage in the future.
Transportation of hydrogen produced offshore through re-used existing pipelines has a number of important advantages over new pipelines: we can move faster towards the roll-out of large-scale production, and it is cheaper saving additional investment in new infrastructure. Above all, re-use has a smaller footprint and is better for ecology and the environment (the landfalls and all interconnections are already in place).
Also read: How Dutch offshore wind farm plans to store energy at the bottom of the sea
Facts and figures of hydrogen transportation by existing pipelines
- The NGT and NOGAT offshore gas pipelines are suitable for hydrogen transportation. Bureau Veritas recently issued both pipelines “Certificates of Fitness” to transport (pure) hydrogen.
- NGT and NOGAT estimate the costs of making the pipelines suitable for hydrogen to be less than ten per cent of the cost of a new pipeline (including additional inspections) which will benefit society and end-users significantly.
- The NGT pipeline landfalls at Eemshaven in Groningen, and the NOGAT pipeline at Den Helder in North Holland. Thus, no new landfalls need to be created through vulnerable natural areas. Moreover, there are already existing connections to the onshore natural gas network.
- The hydrogen transport capacity of the NGT pipeline is estimated to be up to 10-14 GW, and of the NOGAT pipeline up to 10-12 GW.
- By producing hydrogen at sea instead of on land, and then bringing this energy to shore via NGT and NOGAT, investments in up to six to eight new DC power lines (2 GW per line) can be saved.
- One of the two pipelines could be freed up for pure hydrogen transport prior to 2030. The existing natural gas production that is currently transported by NGT and NOGAT can all be accommodated, for example, by the NOGAT pipeline through re-routing. This would enable wind-powered green hydrogen production from wind (search) areas 7 and 3 possible sooner. Another scenario would be to first make the NOGAT available for hydrogen and continue gas production via NGT for longer. This is subject to study work to be performed and subject to all required approvals.
- Re-use of the pipelines can help to enable the early realisation (before 2030) of green hydrogen at sea from wind demonstration projects.
- Empty gas fields, potentially suitable for hydrogen storage, are already connected to the NOGAT and NGT infrastructure. There are also salt rock formations (e.g. domes) near the pipelines that could be used for the construction of offshore salt caverns for hydrogen storage.
- Storage of hydrogen at sea in empty gas fields and/or salt caverns will enable balancing of weather/seasonally-related production fluctuations, allowing the same volume of hydrogen (baseload) to be transported to land every hour of the year all year round.
- Baseload hydrogen transport to land allows an even larger offshore wind/hydrogen production capacity to be connected to the NGT and NOGAT pipelines; approximately 17-24 GW.
- By linking re-used natural gas pipelines for hydrogen transportation with the surrounding North Sea countries, such as the United Kingdom, Denmark and Germany, international exchange, import and trade of hydrogen can be developed and promoted.
- Re-use of physical assets (i.e. pipelines, platforms, and empty gas fields), as well as the organisational and human assets of a standing organisation, that can organise and perform re-use, installation, maintenance, operational and administrative tasks, enables a fast, cheap and reliable transition to hydrogen.
Picture (top): Overview of existing offshore pipelines and wind (search) areas. Red: NGT, blue: NOGAT, yellow: WestGasTransport (WGT).
Also read: North Sea green hydrogen consortium selects companies to study technical feasibility
