Longannet power station
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Longannet power station is a large coal-fired power station on the upper Firth of Forth near the Royal Burgh of Kincardine on Forth, Fife, Scotland. It is the most powerful generating station in Scotland.
When constructed it was the largest and most powerful coal-fired station in Europe, and it is still the second largest, after Drax in Yorkshire, England. It is a regional landmark, dominating the Forth skyline with its 183m (600 feet) chimney stack. Like all other power stations in Scotland it lacks cooling towers, relying instead on river water as a coolant.
Longannet has an installed capacity of 2,400MW (equivalent to 2 AGR nuclear stations) made up from four 600MWe generation units, each featuring a single boiler feeding two 300MWe GEC turbo-alternators, with the steam spaces cross coupled. The declared net capacity is rated at 2,304 MW due to operational losses. On average Longannet produces 10.4 TWh per year and in 2000-2001 achieved the highest generation output in its history by supplying more than 12.25 TWh to the National Grid.
Construction began in 1962 for the then South of Scotland Electricity Board (SSEB) adjacent to the existing Kincardine Power Station. Commissioned in 1972, it was originally supplied with coal directly from its own deep mine at Longannet Colliery. Coal consumption exceeds 10,000 tonnes per day. Longannet colliery, by then the last deep mine in Scotland, was forced into premature closure in 2002 due to flooding. All fuel therefore must now be imported, the majority via the former British Steel ore loading facility at Hunterston Ore terminal in Ayrshire. Onward transport is by rail and the level of traffic required to supply Longannet's fuel demand has caused extreme congestion on the Scottish rail network. An alternative route via Stirling at the mouth of the river Forth is being reopened.
Longannet produces ash at the rate of up to 4,350 tonnes per day, the majority of which is collected and either sold to industry or mixed with water and piped as a slurry to the nearby Preston Island. Here it is deposited in former salt pans, stablised and used to reclaim the land from the Firth of Forth. To improve environmental emissions, Longannet is now fitted with 'Low-NOx' burners to limit the formation of oxides of nitrogen and a 'Gas Reburn system' that uses natural gas to convert NOx into nitrogen and water vapour. Longannet also burns up to 65,000 tonnes of treated and dried sewage sludge per year, which has a similar calorific value to low-quality brown coal.
This facility is now owned and operated by the privatised Scottish Power utility group.
