In Scotland the structure was different, with all aspects of generation, transmission, distribution and supply being carried out by two vertically integrated companies.

In 2000, as part of further restructuring under the Utilities Act 2000, the PES were required to have separate licences for their supply business and distribution network, which were renamed distribution network operators (DNOs).

In 2002 it was sold to Powergen, which was subsequently acquired by the German utility company E.On, and the operations were rebranded in 2004.

Now owned by UK Power Networks along with London Electricity and SEEBOARD.

Originally acquired in 1996 by a consortium of US companies GPU and Cinergy, after a bid by Powergen was blocked by government.

The electricity retail business was sold to National Power in 1999 and continues under the Npower brand.

[7][8] The distribution business that remained was purchased by Powergen in 2004[2] and merged with that of East Midlands Electricity to form Central Networks.

The electricity distribution business is operated by Northern Powergrid, a subsidiary of Berkshire Hathaway Energy.

Merged with North West Water in 1995 to form United Utilities, the electricity businesses of which were subsequently sold, with the retail supply arm of Norweb becoming part of TXU Energi (now part of E.On) and the distribution network becoming Electricity North West.

[12] In 2007 it was acquired by the Spanish energy utility Iberdrola,[4] although it continues to use Scottish Power branding on domestic sales of gas and electricity.

The business was purchased by Welsh Water in 1996, but the company formed as a result - Hyder plc - soon encountered serious financial difficulties[14] which led to its break-up.

The electricity distribution business is operated by Northern Powergrid, a subsidiary of Berkshire Hathaway Energy.