Thanet OFTO
OperationalOffshore GridGB300 MW132 kV28.6 km2010
Basic information
9 fieldsAlso Known As
Thanet Offshore Transmission Owner · Thanet OFTO Limited · TR1 Thanet OFTO
Status
operational
Capacity
300 MW
Project Company
Type
offshore grid
Transmission Model
Developer Build & Transfer
Expected Life
20 years
Website
Supply Chain (9)
Project Timeline (23)
2033Decommissioning Start
Thanet OFTO Limited plans to decommission the Thanet offshore transmission owner asset at the end of its economic useful life in 2033, with decommissioning costs estimated at £7.111 million to be incurred from 2033 onwards. This indicates that decommissioning activities for the transmission system are expected to commence in 2033 following the conclusion of the project’s operational life.
31 Dec 2021Refinancing
Following the discontinuation of the previous interest rate benchmark on 31 December 2021, Thanet OFTO Limited’s senior debt and associated interest rate swaps were transitioned to an alternative benchmark of SONIA plus credit adjustment spread, representing a change in the project’s debt terms, although the company reports that the impact on its financial statements was not material.
Dec 2021Maintenance Other
In December 2021, Thanet OFTO Limited changed its outsourced operations and maintenance (O&M) provider, replacing Balfour Beatty Utility Services (BBUS), which had decided to exit the OFTO O&M market, with EDS HV as the new O&M operator. Balfour Beatty Investments Limited continues to act as an informed buyer to oversee the quality of the outsourced O&M services and ensure compliance with the OFTO licence and good industry practice.
Aug 2015System Restoration
By August 2015, the shallow‑water repair campaign on the Thanet Offshore Wind Farm export cable had been completed, with both inter‑tidal joints successfully installed and the repaired section buried to two metres. Following these works, the export cable system was re‑energised and made available again to the Thanet OFTO, restoring full operational service of the offshore transmission connection, after which the repair barge Pontra Maris demobilised and returned the spare cable reel to Briggs Marine’s depot.
Mar 2015Inspection Survey
In March 2015, Briggs Marine, working with Balfour Beatty T&D, mobilised the survey vessel Solent Guardian to the Thanet Offshore Wind Farm export cable route to conduct fault‑finding and depth‑of‑burial assessments around the inter‑tidal joint area. The shallow‑water survey located the cable fault in the inter‑tidal zone and provided engineering data needed to design an appropriate shallow‑water repair solution for the Thanet OFTO export cable system.
Mar 2015Cable Repair
From March 2015, Briggs Marine undertook a shallow‑water export cable repair campaign for the Thanet Offshore Wind Farm on behalf of Balfour Beatty T&D, addressing a fault near the inter‑tidal joint of the Thanet OFTO export system. The Forth Guardsman vessel with divers, de‑burial and cutting equipment located and cut the cable three metres deep and prepared the ends, while the Pontra Maris barge was mobilised and outfitted with a modular cable repair spread, spare cable reel and burial tool to complete jointing and re‑burial of the repaired section.
23 Feb 2015Major Outage
On 23 February 2015, the intertidal joint of the South Export cable C1 in the Thanet OFTO transmission system failed, causing a significant outage on the export link connecting the Thanet Offshore Wind Farm to shore. This failure at Thanet OFTO, occurring just days before a separate export cable loss at Gwynt y Môr, was highlighted in industry discussions as contributing to insurer concerns about continued coverage for offshore transmission cable risks.
16 Feb 2015Stake Transaction
On 16 February 2015 Balfour Beatty announced the disposal of an 80% equity interest in the Thanet OFTO offshore transmission project to funds managed by Equitix for £40 million, retaining a 20% ownership stake. Thanet OFTO comprises the high-voltage transmission system connecting the 300 MW Thanet Offshore Wind Farm to the onshore grid, including one offshore and one onshore substation and over 50 kilometres of subsea cables operated under a 20‑year Ofgem licence.
Funds managed by Equitix acquired from Balfour Beatty (80%)
17 Dec 2014Other Permit Awarded
Authority: Ofgem · Licence: Offshore Electricity Transmission Licence
On 17 December 2014, The Gas and Electricity Markets Authority (Ofgem) awarded Thanet OFTO Limited an Offshore Electricity Transmission Licence, permitting and requiring the company to maintain and operate the Thanet offshore electricity transmission assets. The licence under the Electricity Act 1989 underpins the OFTO’s 20‑year regulated revenue entitlement starting from the date funds were drawn to acquire the transmission system.
17 Dec 2014Other Permit Awarded
Authority: Ofgem · Licence: Section 10D certification of compliance with EU Third Package unbundling requirements
On 17 December 2014, Thanet OFTO Limited was issued a certificate by the Authority under section 10D of the Electricity Act 1989, confirming that it complies with the unbundling requirements of the EU Third Energy Package as implemented by the Electricity and Gas (Internal Markets) Regulations 2011.