10. NIE Networks
- Chief executive: Nicholas Tarrant
- Pre-tax profit: £52.8m
- Employment: 1,284
- Pay bill: £73.8m
NIE Networks, which owns the electricity transmission and distribution networks in Northern Ireland, increased network investment by 7% last year and agreed its 2017 to 2024 investment plans with the Utility Regulator.
This 2017 investment was primarily to refurbish and replace worn assets and to maintain the reliability and safety of the electricity network for its 870,000 customers.