Electricity Act 1947 Wikipedia
The Electricity Act 1947 was an Act of the Parliament of the United Kingdom that nationalised 505 separate electricity generation and supply organizations in Great Britain on 1 April 1948, both privately owned and state owned, and consolidated them into 14 area electricity boards of the new Central Electricity Authority that the Act created (also known as the British Electricity Authority), which subsequently became the Central Electricity Generating Board. The duty of the area boards was to acquire bulk supplies of electricity from the Central Authority and to distribute electricity economically and efficiently. The Act also transferred the generating assets and liabilities of a number of companies in England and Wales into a single state-controlled body.
Subsequently, the South of Scotland Electricity Board (SSEB), was formed as a result of the Electricity Reorganisation (Scotland) Act 1954 when on 1 April 1955, South West Scotland Electricity Board and South East Scotland Electricity Board were merged.