RWE tests recyclable turbine blade at Kaskasi

4C Offshore | Tom Russell
By: 07/09/2021 RWE
Siemens Gamesa and RWE have committed to installing a select number of wind turbines with recyclable blades at the Kaskasi offshore wind farm off the coast of Heligoland. The 81-meter long blades are designed to enable the recycling of the composite parts into new products at the end of their lifecycle.

For RWE,
Kaskasi will be instrumental in testing the world’s first recyclable blade under operational conditions from 2022 onwards.

Many components of a wind turbine, such as the tower and nacelle parts, already have established recycling practices. Until now, the composite materials used in wind turbine blades have been more challenging to recycle because a resin system binds all components together. In its recyclable blade Siemens Gamesa is using a new resin type, with a chemical structure that makes it possible to separate the resin from other components. The process protects the properties of the materials and so allows them to be reused in new casting applications, for example in the automotive industry, or in consumer goods like flight cases and flatscreen casings.

At its
Kaskasi 342 MW wind farm, RWE also plans to install for the first time ever special collars around three monopile foundations. The steel collars are designed based on a RWE patent and will be installed at seabed level. The space between collar and monopile foundation will be filled with grout material to create a stable connection. RWE will carry out accompanying tests to verify that the collar improves structural behaviour, compared to standard monopiles.

Kaskasi will be the first commercial offshore wind farm in the world to use a new installation method for driving the wind turbine foundations into the seabed to their target penetration depth. In comparison to conventional hammering techniques the innovative vibro pile driving method will speed up the process of installing the foundations, has a gentler impact on the structure while producing far less noise, and reduces impacts on the maritime environment, according to RWE.

“We are pleased that our offshore wind farm Kaskasi is able to provide a fantastic facility for testing innovations; here we are preparing to test special steel collars and to use an improved installation method for foundations. Now, Kaskasi is set to install the world’s first recyclable wind turbine blade manufactured by Siemens Gamesa. This is a significant step in advancing the sustainability of wind turbines to the next level,"
said Sven Utermöhlen, CEO Wind Offshore, RWE Renewables.

The Kaskasi offshore wind farm is to be constructed 35 kilometres north of the island of Heligoland. Once all 38 wind turbines are fully operational at the end of 2022, Kaskasi offshore wind farm will supply the equivalent of approximately 400,000 households with green electricity.

For more information on offshore wind farms worldwide, click here.