Commercial Models for Future Hydrogen Production
There have been several North Sea hydrogen pipeline projects announced recently, with Norway being a potential exporter of low carbon hydrogen by pipeline to the EU.
There is a dense network of offshore pipelines in the North Sea associated with oil and gas production. These lines vary in size and function from small diameter lines transporting reservoir fluids from subsea wells to processing facilities, to large diameter trunklines transporting processed gas from several production facilities to onshore terminals.
The large gas trunklines are the most analogous to what would be needed for large scale hydrogen transport. There are several trans-national export pipelines from Norway to the UK and EU, and two interconnector pipelines between the UK and EU which can operate in either flow direction.
Ownership of these large pipelines is by a small number of companies, with Gassled being the owner of several. With large gas resource and modest native demand, Norway is the major player in the North Sea both in terms of number of pipelines and total export capacity.
Published studies [Bacton Energy Hub, OGTC Re-Use of Offshore Pipelines for Hydrogen, SOWEC] that have reviewed the potential to repurpose offshore gas pipelines for hydrogen transport have concluded that this is unlikely to be feasible for a cross North Sea route, and all offshore hydrogen pipeline concepts that have been published to date are assuming new pipelines will be required.
A significant reason for this is location and size of the existing lines, and the expected long remaining life in hydrocarbon service for the larger lines. While it may be technically feasible to repurpose pipelines, the locations and availability of the suitable lines make this unlikely in the 2030-2040 timescale. Pipelines could potentially be repurposed for storage – 100km of 32” line at 100bar can store approximately 16 GWh (HHV).
Existing gas trunklines have capacities in the range 75 – 300 TWh/year (HHV). This is equivalent (in energy terms) to approximately 2 – 8 Mt/year hydrogen. Export pipeline terminal facilities are expected to include: • Hydrogen reception & metering. • Compression facilities, compressing hydrogen to 70-80 barg. • Depressurisation facilities – these would consist of a facility to allow the contents of the pipeline to be safely evacuated in the event of a significant problem with the subsea pipeline (e.g. a major leak).
Norway also has a history of public ownership of strategic energy infrastructure. It is clear that the potential for import of hydrogen by pipeline from Scotland is not visible on a number of EU / European illustrations of future hydrogen supply routes into the EU, therefore some effort in marketing this concept more widely is recommended.
