List of pre-nationalisation UK electric power companies
The electrical power industry in the United Kingdom was nationalised by the Electricity Act 1947, when over six hundred electric power companies were merged into twelve area boards.
The Board's area was defined as: Leicestershire, Northamptonshire, Rutland and parts of Bedfordshire, Buckinghamshire, Derbyshire, Lincolnshire, Nottinghamshire, Staffordshire and Warwickshire.
† Not listed in the Electricity (Allocation of Undertakings to Area Boards) Order, 1948, presumably had ceased before this date.
The Board's area was defined as: Cambridgeshire, Hertfordshire, Huntingdonshire, the Isle of Ely, Norfolk, Suffolk and parts of Bedfordshire, Buckinghamshire, Essex, Middlesex, Oxfordshire and the Soke of Peterborough.
The Board's area was defined as: The administrative County of London and parts of Essex, Kent, Middlesex and Surrey.
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