The world's largest cable-laying ship is in Dublin to work on the first direct electricity line between the Republic of Ireland and Britain.
The EirGrid East West Interconnector will cost around €600m, and is expected to be finished by autumn.
The company says it will allow enough power to supply 300,000 homes to be transported and traded between Ireland and Britain.
The additional 500 megawatts of electricity will also open up a new market for energy exports, particularly exports of Irish wind energy.
The work on the interconnector involves laying 180km of undersea cable and around 80km of cable underground to enable the flow of electricity in both directions.
The huge cable-laying ship was due to depart Howth Harbour and begin laying the cable this morning.
