Triton Knoll Makes Further Onshore Infrastructure Cuts

Illustration; Image source: innogy/ archive (The image is showing the IEC, which has been removed from the wind farm design in the meantime.)

Triton Knoll Offshore Wind Farm Limited has reduced the number of onshore cable circuits required for electricity transport from the offshore wind farm to the national grid. According to the project team, this will help reduce the overall construction footprint of the project and realise planned reductions in costs.

“Our design optimisation, carried out in partnership with UK contractors J Murphy & Sons and Siemens Transmission & Distribution Ltd, is continuing to help deliver the cost and impact reductions anticipated by the project. We’re very pleased to be able to deliver maximum power from this decreased number of circuits, thereby reducing the project’s local construction footprint,” Julian Garnsey, innogy’s Triton Knoll Project Director, said.

The cable network of the onshore electrical system is being constructed in two sections, and connects the offshore network to the onshore national grid distribution network.

A reduction from six circuits of three cables each to two circuits of three cables each at 220kV in order to transmit the High Voltage AC (HVAC) electricity from the transition joint bays at the landfall near Anderby to the proposed Triton Knoll onshore substation. This section of the onshore cable will be installed by onshore cable contractor J Murphy & Sons (JMS).

A reduction from four circuits of three cables each to two circuits of three cables each at 400kVin order to transmit the electricity from the new Triton Knoll onshore substation to the existing National Grid substation at Bicker Fen, Boston. This section of the route is managed by substation contractor Siemens Transmission and Distribution Ltd (STDL).

The onshore infrastructure move follows the removal of the planned Intermediate Electrical Compound (IEC) in September 2017, which was originally expected to be built near Orby.

When it comes to the project’s offshore design, in February 2018, Triton Knoll filed an application to the UK’s Secretary of State for Business, Energy and Industrial Strategy (BEIS) seeking to make changes to the project’s Development Consent Order (DCO). These include decreasing the capacity of the offshore wind farm from ‘up to 1,200 MW’ to ‘up to 900 MW’, decreasing the number of wind turbines from ‘up to 288’ to ‘up to 90’, decreasing the number of collector substations from ‘up to 4’ to ‘up to 2’, and removing the meteorological stations and the option for HVDC substations.

Triton Knoll, owned and developed by innogy, has a planned installed capacity of 860MW. The project is now progressing towards a financial investment decision later this summer with full onshore construction starting shortly after, and offshore construction starting in late 2019. First energy generation could be as early as mid-Q1 2021, with the project expected to begin commissioning in 2021.