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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 Regulatory Accounts 2022-23

    Size: 15 MB Download
  • DTPWE Basis of Transmision Owner Charges 2023-24 - Issue 5

    Size: 155 KB Download
  • DTPWE Annual Compliance Report

    Size: 571 KB Download
  • DTPWE Separation and Independence of the Transmission Business Compliance Statement_V8

    Size: 717 KB Download
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