Transmission Workstream DN Interruption Update - Introduction Mark Freeman 3 January 2008

DN Interruption Update Mod 0174 – revised tender timescale Implemented 29 Nov Incentives GDPCR Final Proposals 4 Dec 07 Ofgem Economic Test note 25th October Interaction with NTS Exit Reform Mod 0090 is stand alone Automated tender system being developed by xoserve Testing to start 11th Feb 08 Key Dates

DN Interruption Update Key Dates Further Customer Engagement Dec 07 – Mar 08 UAT Start 11 Feb UAT Finish 21 Mar Feb Mar Apr Site Eligibility Notification 1 Apr May Jun Jul Aug Sep Oct Tender Opens 2 Jun Tender Closes 13 Jun Apply for NTS capacity NTS capacity results Publish Requirements 1 May Notify Results 31 Jul Comments on Interruptible Capacity Methodology close out 20th Dec 07

Transmission Workstream DN Interruption Update - Introduction Mark Freeman 3 January 2008