<strong>EirGrid</strong> <strong>plc</strong> <strong>Annual</strong> <strong>Report</strong> & Accounts <strong>2011</strong> Development East West Interconnector The East West Interconnector is an <strong>EirGrid</strong> project co-financed by the European Union, to provide a submarine electricity link between the Irish and UK power systems. The project is an HVDC (High Voltage Direct Current) link with a capacity of 500MW, running from Woodland in County Meath, to Deeside in North Wales, near Liverpool. The project comprises an overall cable route length of approximately 260km (45km on land in Ireland, 180km submarine, and 35km land route in Wales), along with converter stations at each end of the cable, providing connection to the UK and Irish alternating current systems. Work progressed to schedule across all parts of the project in <strong>2011</strong>. Ducting of the land sections is largely complete, and cable installation, jointing and grouting are ongoing. The converter stations are well advanced with civil works largely completed and delivery of main electrical equipment to site well underway. Laying and burial of the marine cable section commenced in <strong>2011</strong>, with approximately 80km of the marine section now complete, which is fully in line with expectations. Work on a storage facility to hold spare marine cable at Liverpool dock is also underway and proceeding to schedule. Laying of the remaining 100km of marine cable will commence in April 2012, and the project remains on schedule for completion, within budget, by the end of 2012. Grid25 Grid25 is the programme for the development of the transmission system in Ireland, to meet future demands in the period to 2025 and beyond. Grid25 includes projects in construction, projects in public planning, and projects still under investigation and optimisation. The programme includes construction of over 800km of new transmission circuits, and the upgrade of over 2,000km of the existing transmission system. During <strong>2011</strong>, approximately 80km of new circuits were completed, over 300km of existing circuits were upgraded and 160km of new circuits were at an advanced construction stage and expected to be complete in 2012. There were a number of major new station and circuit projects completed during <strong>2011</strong> including significant transmission works in the Cork Harbour area and in counties Wexford, Kildare and Kerry. New High Temperature Low Sag (HTLS) conductor technology was used for the first time on the Irish network, resulting in the ability to increase the rating of an existing circuit by 50% or more. These major investments will provide substantial increased capacity to the local areas and position them for the development of new electricity demands or generation. The introduction of the HTLS conductor, along with continued optimisation of the Grid25 programme has resulted in a re-estimation of the overall cost of Grid25 from €4 billion to €3.2 billion. This is an important saving which will result in lower tariffs for all electricity customers in Ireland. Work progressed during the year on construction of projects which will ensure continued reliable supply, when complete, to towns and surrounding areas including Mullingar, Tullamore, Roscommon, Galway, Sligo, Meath, Cavan and Offaly. A number of major projects are in, or are entering, the public planning phase, including major developments to improve supply to and from the Mayo/Galway region, in counties Dublin, Laois and Kerry, and to increase capacity along the major power corridor between Dublin and Cork. 26
<strong>EirGrid</strong>’s Director of Grid Development Andrew Cooke with the Minister for Communications, Energy and Natural Resources, Pat Rabbitte TD viewing cable laying for the East West Interconnector 27