Event archive

Event Organiser: Offshore Engineering Society

Floating Substations for gigawatt-size floating windfarms, London

  • Lecture
  • London
  • 06 October 2021
  • 18:00 - 19:30
Floating Substations for gigawatt-size floating windfarms, London

About this event

Floating wind farms are expected to become an important contributor to offshore wind energy production over the next decade and beyond, with a UK target of 1GW of installed capacity by the end of the decade. Currently, there are a few floating wind farm demonstrator projects that transmit power directly to shore.

As floating wind farms move from pilot projects to commercial-scale installations they will move further offshore and into deeper water. There will be a requirement for offshore substations to transmit the power to shore, for which floating structures will be the preferred solution because of the water depth. This presentation describes preliminary designs of commercial-scale floating substations, together with indicative economic comparison of floating vs fixed installations at various water depths.

Two different floating substation concepts were developed, for AC and DC substations of 1.2GW capacity. The larger topsides footprint and greater mass of the HVDC conversion equipment make a conventional semi-submersible hull form efficient when combined with a stressed-skin topsides structure. The smaller footprint, lighter weight and lesser requirements for protection from the elements for the HVAC topsides make this inefficient, so a deep draught semi-submersible was the preferred solution.

Layouts for the electrical and ancillary equipment were initially developed, to enable efficient packaging for the topsides. By integrating the hull and topsides, the overall mass of the structures were minimised, benefitting stability and reducing hull size. Hydrodynamic analysis of the substructures was performed and structural code checks on the hull and topsides were carried out in Sesam. Mooring designs for each structure for 350m water depth were developed and analysed in Orcaflex.


Justin Jones

Civil and Structural Group Leader, Petrofac Engineering and Consultancy Services

Justin Jones

Justin has more than 20 years’ experience in engineering consultancy across many industries including renewable energy, oil and gas, power generation, infrastructure and defence. Justin is the Civil and Structural Group Leader in Engineering and Consultancy Services in Woking and provides technical leadership in advanced engineering analysis across Petrofac.

Areas of expertise include dynamics, blast, geometrically non-linear analysis and plastic analysis. He has particular experience of fatigue analysis of structures and moorings including chain out-of-plane bending analysis.

He has worked extensively in the renewables sector, on a variety of different projects such as wind turbine structural analysis, wind turbine ground borne vibration, the Pelamis and Oyster wave energy converters, fixed and floating offshore substation concept design, dynamic cable analysis and non-linear analysis of offshore substation grouted pile connections.

Event venue

Institution of Civil Engineers
One Great George Street
London SW1P 3AA
United Kingdom

For more information please contact:

Elira Alushi

e: [email protected]