Electricity Act 1989

The Electricity Act 1989 provided for the privatisation of the electricity supply industry in Great Britain, replacing the Central Electricity Generating Board in England and Wales and in Scotland by the South of Scotland Electricity Board and the North of Scotland Hydro-Electric Board. The Act also established a licensing regime and a regulator for the industry called the Office of Electricity Regulation (OFFER), which has since become the Office of Gas and Electricity Markets (OFGEM).

...
Wikipedia