Offshore substations for efficiency and safety

To help the wind farm work more efficiently, two offshore substations have been installed as part of the first 630MW phase of London Array. These will collect power from groups of wind turbines before feeding it to shore using the main export cables.

The offshore substations consist of the following components:

• Transformers to boost the power to a higher voltage before it’s brought ashore. This helps reduce the amount of electricity that’s lost during transmission.
• Switchgear and emergency equipment that make it safe for us to operate the wind farm.
• A back-up electrical generator and batteries.

Building the substations

Future Energy (a joint venture between Fabricom, lemants and Geosea) designed, built and installed the substations with the electrical equipment supplied by Siemens Transmission and Distribution Ltd.  Each offshore substation topside is identical. Each topside consists of three levels, with an area of around 20m x 20m. As each assembled and fully equipped substation topside weigh’s around 1,250 tonnes, we used the heavy lift vessel, ‘Rambiz’, to install them.