42. System Operator Northern Ireland
- General manager: Robin McCormick
- Pre-tax profit: £9.4m
- Employment: 129
- Pay bill: £7.8m
SONI is the transmission system operator (TSO) of the electricity grid in Northern Ireland. The grid provides the high capacity ‘motorway’ for transporting electricity.
SONI was founded in 2000 and is regulated by the Utility Regulator.