" Provisional data for 2017 show Northern Ireland import and export volumes were similar and also, again, overall export and import volumes are relatively low compared to total electricity consumption. In addition, unlike the previous three years, Northern Ireland exported more electricity to the Republic of Ireland than it received in imports in 2017"

https://www.economy-ni.gov.uk/sites/default/files/publications/economy/energy-northern-ireland-2018.pdf