we have an excess of water,most of which is wasted. contrast Norway, who have been using see here
Of the total production in 2007 of 137 TWh, 135 TWh was from hydroelectric plants, 1 536 GWh was from thermal power, and 892 GWh was wind generated.[1] In same year, the total consumption was 115 TWh.[2]

The annual electricity consumption was about 26-27 MWh per inhabitant during 2004-2009 when the European union (EU15) average in 2008 was 7.4 MWh. Norway's consumption of electricity was over three times higher per person compared to the EU 15 average in 2008. The domestic electricity supply promotes use of electricity.
why is it not possible for ireland to sell excess water , to countries who are short of it