Offshore electricity transmission GB SQSS review Monday 3

Offshore electricity transmission, GB SQSS review Monday 3 rd July – Andy Hiorns

Introduction Sub-group objectives ·Assess the relevance of the existing onshore GB SQSS for application to offshore transmission networks ·Provide recommendations to OTEG identifying feasible options for security standards relating to offshore transmission networks. Note : Amendments to onshore standards are out of scope of this group Timescales ·Submit recommendations to OTEG late August

Proposals ·Focus on most relevant areas of GB SQSS – ·Generation connection criteria ·Customer choice variations ·Voltage Compliance ·Establish appropriate deterministic level for generation connection criteria by cost benefit analysis ·Formulate network models ·Populate with real system data ·Carry out cost benefit analysis on these models

Methodology for analysis Shore Generator Onshore Grid Offshore transmission circuit Offshore System TO Entry Point Grid Entry Point or Users System Entry Point Offshore transmission circuit 40 km Cable £ 50 m installed 98% reliability Issues to consider: Generation 250 MW Windfarm 30% load factor ROC value £ 60/MWh Cable is assumed unavailable 2% of time Generation is at full output 30% of the time Losses – Revenue / Electrical Benefit gained by installation of additional circuit capacity

Work in progress ·Proposed network models for analysis presented in paper GB SQSS 1. Paper agreed at 2 nd subgroup meeting 27 th June 2006. ·Defining exact data requirements before carrying out cost benefit analysis. ·Population of network models in progress. ·Compiling data and maintaining documents with all information received. ·Regular progress meetings planned to ensure agreement of work in progress. ·All assumptions made during the analysis to be noted and accompany sub group recommendations. ·Meeting notes and discussion papers published on DTI and Ofgem websites as produced.

Issues noted to date ·Requirement to assess impact that offshore security can have on onshore transmission network capability to meet ACS demand. ·Updates to technical codes will follow the GB SQSS review work. ·Commercial frameworks will follow once optimum design solution has been established ·Use of system charges ·Access rights ·Interface concerns with DNO connections between onshore and offshore TO.