Siemens Energy, lead contractor for the construction of National Grid’s Viking Link interconnector project, has worked with GeoPura to provide off-grid power and heat to the project’s construction site for the first time. A world first, this has been achieved through the installation of a zero-emission hydrogen fuel cell.
Viking Link is a joint venture between the UK’s National Grid Ventures and Energinet, the owner and operator of the Danish electricity system.
The goal of the joint venture is to build a high-voltage electricity interconnector, which, when completed, will be the longest in the world: it will stretch over 865 kilometres between Lincolnshire in the UK and Revsing in Southern Jutland, Denmark. This will enable the sharing of clean energy between the two nations and contribute to the UK’s 2050 ‘net zero’ goal.
Powering the Viking Link Site
The site requires off-grid power and heat because it will be six-to-eight months before it has a grid connection, and there is also the potential for the period to be lengthened further by Covid-related disruptions and delays. In the meantime, the hydrogen fuel cell system will be able to provide enough energy and heat for the construction village, eliminating the need for noisy and dirty diesel generators.
The construction village, which contains portacabins, housing offices, and other facilities, will be used by Siemens Energy employees and other contractors carrying out work on the project. Starting off with an access road, work is scheduled to begin on the converter station for the new interconnector later this year. Siemens says that the hydrogen fuel cells will be capable of providing enough heat and power for all 20 of the village’s cabins. They’re not just powering buildings, either: there will also be six electric vehicle charging stations to allow workers to ‘drive cleaner’.
Construction work has begun at the under-construction Viking Link site in Lincolnshire, pictured above. Image Credit: National Grid.
Utilising Waste Heat
First demonstrated at the Goodwill Festival of Speed in 2019, the fuel cell has since been developed further to utilise waste heat generated by its own cooling system, which would otherwise be lost. The waste heat is passed via a heat exchanger to heat up water that is then sent through to heat two drying rooms for the site workers’ clothing and personal protective equipment (or PPE).
Siemens says that the fuel cell system will be able to provide 250 kilovolt-amperes of standard three-phase, 400V electrical power—comparable to that provided by diesel generators—and up to 80 kilowatts of heating for the site’s 20 portacabins. The system also has 216 kilowatt-hours’ worth of battery storage, which will prove vital to smooth out the peaks and troths of general power demand and improve the system’s overall efficiency. The battery power also means that if the hydrogen supply is interrupted, the system’s output will remain unaffected and power will continue to be provided for several hours.
According to Siemens, the fuel cell system is based on a single 20-foot shipping container. This houses all the necessary equipment for converting hydrogen into electricity and heat. Around 300 metres of reusable piping has been installed at the site to distribute the hot water from the fuel cell system to the cabins and drying rooms.
Initially, the hydrogen supplied for the fuel cell system will be derived from conventional sources, but once a sustainable supply of a green alternative is available, those conventional sources will be replaced. By using green hydrogen at the Viking Link site, it has been estimated that around one tonne of CO2 will be saved on a weekly basis.
The UK’s energy minister, the Right Honourable Kwasi Kwarteng, said: “Hydrogen has a key role to play in the UK’s journey to net-zero carbon emissions, and I’m delighted to see this innovative off-grid power source being installed at Viking Link.
“It’s steps such as this that will be vital in enabling a hydrogen economy to flourish in the UK, as we build back better with new low-carbon jobs.”