Scottish and Southern Energy plc (LSE: SSE), known as SSE, is a British-based energy company. Its headquarters are in Perth, Scotland. It is listed on the London Stock Exchange and is a constituent of the FTSE 100 Index. It is one of the leading energy companies in the UK and the country’s second largest energy supplier, ranking 23rd in the FTSE 100 on 31 March 2009. It is involved in the generation and supply of electricity, the supply of gas, the operation of gas and telecoms networks and other energy-related services such as gas storage, contracting, connections and metering. It entered into the hydrocarbon exploration and production sector in April 2010.
SSE is the UK's largest generator from renewable sources.
The company was formed in 1998 following a merger between Scottish Hydro-Electric and Southern Electric.