Ørsted, a global leader in offshore wind energy, has finished construction of its first large scale UK battery energy storage system (BESS). This is the latest milestone along the path to it becoming fully operational.
There are now 170 megapacks in place alongside the onshore converter station for Ørsted’s Hornsea 3 offshore wind farm, near Norwich, Norfolk. Each is the length of a classic Routemaster London bus but weighs the same as five buses.
The system – known as Iceni after the Norfolk-based warrior tribe of the Roman era – will have a capacity of 600 MWh (and a 300 MW power rating). This is equivalent to the daily power consumption of 80 000 UK homes.
The Iceni team comprises specialists from Ørsted, Hitachi Energy, Knights Brown, and Tesla working together on this first of its kind project. What makes this BESS unique is the split layout of the site with the two areas, separated by the Hornsea 3 onshore converter station, linked by 18 x 33 kV cables, each over 600 m in length. In addition, the shared grid connection point with Hornsea 3 has added additional technical complexity over a stand-alone connection point to the National Grid.
The project is now in the final stages of the mechanical and electrical installation with the 33 kV cross site cables currently being installed and terminated. The first stage of commissioning and testing is well underway, and preparations are being made for energisation of the BESS transformer.
When completed, the BESS will be one of the largest in Europe.
Beatrice d’Eufemia, Project Manager for Iceni BESS at Ørsted, commented: “It is a milestone moment for Ørsted that construction is now complete on our first large scale BESS in the UK. The system will make the best use of renewable energy produced in the UK as when electricity generation exceeds demand, the excess can be stored and then used when demand is greater, helping balance the grid and lower electricity costs for everyone.”
Richard Swann, Construction Manager for Iceni BESS at Ørsted, added: “It’s a real testament to the hard work, dedication, and co-operation of the team from many different organisations that the construction has been completed successfully.”
David Shillabeer, Head of Transmission & Distribution at Knights Brown, concluded: “Reaching this milestone is a significant achievement for everyone involved in the Iceni project. Delivering a BESS of this scale has required close collaboration between Ørsted, Knights Brown, and the many other organisations that have contributed to its success. Beyond the engineering, the scheme has enabled us to invest in local people, develop skills, and create opportunities across Norfolk and the wider region. We are proud to have played our part in an important project that will support the UK’s transition to a more resilient, low-carbon energy system, while leaving a positive legacy for the communities in which we work.”
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