Strangford tidal power station

SeaGen
	SeaGen in operation (note the dead water caused by the strong tidal currents )
	location
	Northern Ireland , UK
Coordinates	54 ° 22 '7 " N , 5 ° 32' 46" W Coordinates: 54 ° 22 '7 " N , 5 ° 32' 46" W.
country	Northern Ireland / UK
Waters	Strangford Lough
	Data
Type	Tidal power plant; ( ocean current power plant )
Primary energy	Hydropower ( tides )
power	approx. 2 × 0.6 = 1.2 MW
operator	Sea Generation Ltd. ; (Subsidiary of Marine Current Turbines Ltd. , ; which in turn has been owned by Siemens Business since March 2012 )
Start of operations	2008
Shutdown	2017
turbine	2 × propeller turbine

The Strangford tidal power plant ( also called SeaGen for short by the operator Sea Generation Ltd. ) was a tidal power plant of the type ocean current power plant (i.e. without a dam) in the Strait of Strangford , County Down , Northern Ireland .

Through this strait, which connects Strangford Lough to the Irish Sea , water flows with every high tide, and the current reaches a steady speed of more than 5 knots (2.4 m / s). From this, SeaGen generated an output of around 1.2 megawatts with two axial turbines, making it the most powerful ocean current power plant in commercial operation in 2009.

technology

The most important technical data of the system:

The two rotors were closely based on modern wind turbines . Each had a diameter of 16 m, a weight of 27 t and a maximum electrical output of 600 kW. The angle of attack of the wings was adjustable so that they could be adapted to the current. The rotors rotated nominally at a speed of up to 14.3 revolutions per minute. The speed for the generator was converted to 1000 revolutions per minute via a gearbox.
The traverse (the crossbeam) to which the two rotors were attached was 29 m long and, including the rotors, weighed 150 t. The traverse with the rotors could be lifted out of the water for maintenance purposes using a hydraulic lifting system.
The tower standing in the water had a height of 40.7 m above ground and a diameter of 3 m. The water at this point - depending on the tide - is between 24 and 28.3 m deep (tidal range 4.3 m). The flow speed averages 3.7 m / s (7.2 kn) and a maximum of 4.8 m / s (9.3 kn).

Rotors lifted out of the water for maintenance
Location on the Strait of Strangford (marked by a red star)

history

SeaGen is a development by Marine Current Turbines (MCT) of Bristol . The system was based on the predecessor model SeaFlow , a pilot system with 300 kW output and only one rotor, which was installed by MCT in May 2003 off the coast of North Devon in south-west England. Previously, in 1994, a small test facility with 15 kW was tested in Loch Linnhe , on the west coast of Scotland.

SeaGen was manufactured and pre-assembled by the Harland & Wolff shipyard in Belfast . From here the system was transported to Strangford, where the system was built in April 2008. In July 2008, electricity was fed into the grid for the first time. During the further commissioning, a rotor was overloaded and damaged due to a control error, so that the system was initially only able to work at half its capacity. By December 2008 the damage had been repaired and SeaGen then delivered full power. In regular, commercial operation, 6 GWh were fed in until 2012. The dismantling began in 2016 and ended in 2017.