Facts and figures about the wind farm

Trianel Wind Farm Borkum

Trianel Wind Farm Borkum consists of 40 Adwen AD5-116 (formerly known as Areva Wind M5000) wind turbines with a total capacity of 200 MW. Each wind turbine has an output of 5,000 kW. The wind turbines with a total height of 148 m from the waterline to the blade tip consist of a nacelle, the rotor star and the tower. Calculated from the seabed, the turbine is just under 178 m high and thus taller than Cologne Cathedral (157 m).

At a height of 90 m above sea level, the nacelle, which weighs around 200 t and covers an area of about 88 sqm, houses the main technical equipment for energy conversion: the gearbox, the rotor bearing and the generator.

The rotor star has a total diameter of 116 m and thus covers an area of about one and a half soccer fields. As the rotor star rotates, the energy of the wind is first converted into mechanical energy and then into electrical energy in the generator. The wind turbines shut down at wind speeds above 25 m/s, which corresponds to wind force 10, for protection. At full power, the rotors rotate around their own axis around 15 times a minute at a blade tip speed of around 320 km/h.

Location and facts

Location	Southern German Bight, north of 54º latitude
Distance from the coast	45 km off the island of Borkum
Water depth	25–35 m
Number of wind turbines	40
Installed power	200 MW
Power generation per year	700 GWh
Full utilisation hours	3,500 h per year
Households per year	Electricity generation sufficient to supply, on a theoretical basis, 200,000 households per year, based on an assumed consumption of 3,500 kWh per household per year.
Required space	56 km²
Operation time limit	25 years
Start of construction	September 2011 (phase 1 of the expansion, construction approved in December 2010)
Beginning of continuous operation	September 2015
Shareholders	28

Location of the wind farm

Technical data

Type of wind turbine (WTG)	Adwen AD5-116 (formerly Areva Wind M5000)
Net power	5 MW
Total height from waterline	148 m
Total height from sea bottom	178 m
Hub height	90 m
Rotor diameter	116 m
Total weight	> 1000 t
Rotor weight	110 t
Nacelle mass	200 t
Foundation structure	Tripod
Tripod height	around 45 m
Piles length (Tripod)	25–30 m
Piles diameter (Tripod)	around 2.5 m

Park Overview Map

Operational data

Rated power	5 MW
Switch-on wind speed	3.5 m/s (wind force 3)
Nominal wind speed	12.5 m/s (wind force 6)
Shutdown wind speed	25 m/s (wind force 10)
Speed	5.9–14.8 rpm
Blade tip speed	90 m/s (324 km/h)

Tripod

The firm anchorage on the seabed

The tripods anchor the wind turbines firmly to the seabed. The steel structures, which weigh up to 900 t and are around 45 m high, were “nailed” to the seabed using 25–30 m long steel pipes with a diameter of around 2.5 m, known as piles. In a process called prepiling, the steel pipes weighing up to 100 t were first placed exactly at the appropriate points on the seabed using a pile-driving template, and each pile was driven into place with up to 3,000 hammer blows. The tripods were then placed on the steel nails with millimetre precision. A total of around 48,000 t of steel were used for the wind farm’s foundation, consisting of 40 tripods and 120 steel nails.

The Trianel Substation

The "socket" of the wind farm

The wind farm’s internal substation is its “socket”. The substation, which is located 20 m above sea level on two decks, houses two large transformers. These convert the electricity produced from the 33 kV voltage level to the 155 kV voltage required for transmission to the grid. Trianel Wind Farm Borkum shares the substation with its sister wind farm Trianel Wind Farm Borkum II.

Grid connection (TENNET)

The transport

The DolWin alpha converter platform with a capacity of 800 MW is the heart of the grid operator TenneT’s offshore grid connection DolWin 1. With a height of 42 m and a footprint of around 2,600 sqm, it has an impressive size. Here, the three-phase current produced at the Trianel Wind Farm Borkum is converted into direct current and then transported onshore via a 75 km long submarine cable. The wind power reaches the Dörpen West converter station via a further 90 km long land route.

Converter Station Dörpen West

The conversion

At the Dörpen West converter station in Emsland, the direct current from the grid connection in the North Sea is converted back into three-phase current and finally fed into the transmission grid. In this way, the electricity from offshore wind reaches consumers.