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Walney Ext OFTO


The Walney Extension OFTO is situated in the Irish Sea about 35km off the Blackpool coast.

The OFTO is a 660MW connection between the generators and onshore transmission system

The  two offshore substations are connected to shore by two undersea cables which are up to 76km long, which come ashore in Heysham. The onshore cables, which are about 4km long, connect to the onshore substation at Middleton.

Downloadable Documents

  • DTP WE Decommissioning Programme

    Size: 1 MB Download
  • DTPWE Transmission Licence

    Size: 1 MB Download
  • DTPWE Annual Compliance Report

    Size: 543 KB Download
  • DTPWE Separation and Independence of the Transmission Business Compliance Statement Issue 6

    Size: 705 KB Download
  • DTPWE Regulatory Accounts 2021-22

    Size: 3 MB Download
  • DTPWE Basis of Transmision Owner Charges 2022-23 - Issue 4

    Size: 629 KB Download
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