FAB link receives UK go-ahead

The FAB Link project (France – Alderney – Britain) is to build an electrical interconnector underwater and underground between France and Great Britain via the island of Alderney off the French coast. Originally it was intended to make landfall in Alderney but that plan is not now fixed. An alternative seaward route to the east of the island has been devised to allow for planning restrictions on the island. This does not however preclude the future connection of tidal generation in Alderney waters.

The line will consist of two pairs of conductor cables, with a converter station and connections into the 400 kV AC grids at each end. It will cover nearly 220 km between the electrical substations at Menuel, on the Cotentin peninsula in France, and Broadclyst near Exeter, in England. It is being jointly developed by the French TSO RTE, and FAB Link Ltd in the UK.

At present there are two interconnectors linking the UK & the Republic of Ireland to the rest of Europe, both crossing the English Channel at its narrowest point near Dover and aggregating as 3000 MW. This represents less than 5% of existing electricity generation capacity in these countries, but is low compared to the 10% benchmark proposed by the European Commission and there is strong consensus that this gap should be filled.

The FAB link, which allows a maximum transmission of 1400 MW, will help to meet the perceived need to increase energy trade between the two countries and thus contribute to the energy transition in Europe. This being so it has been recognised as a ‘Project of Common Interest’ by the European Union following support received from both the French and UK governments, and has received funding from the European Commission through the Connecting Europe Facility. The project is also designed to provide a route to market for marine renewable energy planned to be constructed in the seas around Alderney.

There has been a delay in the original project schedule caused by uncertainty over meeting EU regulations in the aftermath of Brexit (the term used to describe Britain’s exit from the EU) and the project is now scheduled to commence construction in 2019 with completion in 2022.

The tender process for main contractors, which was due to be finalised in December, has been delayed for the same reason, but the FAB Link board is confident that the new 2019 schedule will be met.

Components

The main components of the FAB Link line are two pairs of 320 kV high voltage DC submarine cables, each nearly 170 km long, two pairs of 320 kV high voltage DC underground cables in two sections, that is 25 km in France to reach the converter station adjacent to the 400kV Menuel substation and 15km in England to reach the converter station at Broadclyst.

Other components are two pairs of high voltage AC underground cables to cover the 5 km between the UK converter station and the 400 kV Exeter substation, and an underground chamber at each landing junction to connect the submarine and terrestrial cables.

Planning approvals

In January the project received approval from the UK authorities with the granting of a licence from the UK’s Marine Management Organisation, which will allow FAB Link to build and maintain the proposed subsea interconnector within UK waters. The project had already received UK land side approval when East Devon District Council gave outline planning permission for the UK converter station near Exeter International Airport after issuing a certificate of lawful development allowing the electricity cables to be laid underground between the landfall and the National Grid substation near Broadclyst.

The Brexit effect

A delay in the originally envisaged schedule was introduced in December when the French energy regulator said it needed more clarity on the conditions of the UK’s exit from the European Union. The CRE (Commission de régulation de l’énergie/Regulatory Commission of Energy) wrote to the FAB Project’s French partners, RTE (Réseau de Transport d’Electricité), saying it was not yet in a position to offer its support to future electricity interconnector projects between Britain and France beyond those already approved.

Nevertheless FAB Link directors remain confident in the long-term economic case for increased trade in electricity between Britain and France. James Dickson, FAB Link project director, commented: “Given that regulatory support is an essential part of the project, this decision will inevitably lead to a delay to our programme of development and subsequent construction. We are studying the CRE’s announcement in detail and are exploring all options to ensure the project achieves a final investment decision as quickly as possible. We remain committed to finding the best way to proceed so we can complete this project of international importance.”

Landfall options

A marine reconnaissance survey was commissioned in 2014 to identify seabed conditions on the approach to landfall options, helping to refine cable installation techniques and identify environmental sensitivities. The survey identified that a number of sites would not be feasible from a technical point of view. In parallel with the survey, FAB Link also carried out consultation to better understand specific environmental and planning constraints. Detailed seabed surveys carried out in late 2015 and early 2016 confirmed the selected sites as being appropriate, concluding that Budleigh Salterton was the bast landfall in the UK, and Corblets Bay and Longis Bay the preferred landfalls on the northern and southern Alderney coasts respectively.

Route decisions

In October 2014, four offshore route options were explored and optimised to avoid unexploded ordnance (UXO) dumping grounds, mussel farm development sites and identified shipwrecks in close proximity. Technical constraints were also taken into consideration such as minimisation of pre-lay seabed preparation requirements; minimisation of post-lay seabed and cable works requirements; and minimisation of subsea cable crossings. The offshore route selected between Budleigh Salterton and Corblets Bay offered the least constrained option both technically and environmentally. A similar exercise was carried out in the same month on the French side for the Alderney to Le Platé line section, and following installation and cost analysis it was decided that the direct route was the preferred option. The route was subsequently altered following an Alderney Renewable Energy (ARE) request to avoid passing directly though future tidal farm development blocks.

The initial cable route was proposed to be via the Channel Island of Alderney with a 1 km section of underground high voltage DC underground cable but in April 2017, delays and uncertainties relating to the consenting process in Alderney were identified which led to an alternative offshore cable route being developed to the east of Alderney. This (decision pending) option removes the consenting risk associated with Alderney but does not preclude the future connection of tidal generation in Alderney waters.