ABB have won an order worth $550 million to connect the Irish and U.K. power grids using technology that will strengthen the reliability and security of electricity supplies in each country and enable Ireland to expand its wind power capacity.
Eirgrid, the Irish transmission system operators, have ordered a 500MW transmission system using HVDC Light (high-voltage direct current), an ABB technology with environmental benefits that include neutral electromagnetic fields, oil-free cables, low electrical losses, and compact converter stations.
The solution also provides features such as ‘black start’ capability, a way of restoring power after a blackout without the aid of external energy sources.
The transmission link will run underwater for 186km and underground for 70km, with minimal environmental impact.
The only visible parts will be the converter stations at each end that switch AC (alternating current) to DC (direct current) and back. The cable will be encased in extruded polymeric insulation, providing strength and flexibility needed to endure the severe conditions of the Irish Sea. This HVDC Light link is rated at 200kV.
The higher voltage enables a transmission capacity of 500MW. ABB will be responsible for system engineering, including design, supply and installation of the sea and land cables, and both converter stations.
The system is scheduled to be operational in September 2012. Ireland plans to expand wind power generation and this link, between North Dublin and Wales, will ensure that it is able to import power if needed when the wind is not blowing, and to export power to the U.K. when it generates a surplus.