Balmoral Unveils Scour Protection Solution That Replaces Rock Dumping

Innovation

Aberdeen-based provider of buoyancy and protection systems to the fixed-bottom and floating offshore wind industries, Balmoral, has launched a new solution for which the company says can drastically reduce scour phenomena around fixed wind turbines that cause seabed erosion and a reduction in foundation strength and stiffness.  

The scour protection system, called Balmoral HexDefence™, integrates seabed protection and flow reduction to minimise offshore operational costs and potential cable failure, according to the company.

The structure eliminates the requirement to dump rock, instead providing a non-invasive approach to protecting the monopile and the immediate surrounding area, Balmoral says.

Furthermore, HexDefence has lightweight advanced composites construction and allows for streamlined installation method, which makes it easy to install without the need for additional vessels. This helps achieve an improved carbon footprint for all operations, the company pointed out.

Balmoral says its new system is also capable of use with antifouling coatings and does not require special equipment for end-of-life recovery.

“The interlocking panels are generally 10m long and custom-sized to fit varying monopile diameters and feature integrated lifting and access points. In simple terms, the installation process involves sinking the foundation, sleeving it with HexDefence, fitting the transition piece and assembling the pylon and blades”, said Fraser Milne, Balmoral’s engineering and projects director.

“The system is also suitable for retrofitting to existing monopile structures.”

Balmoral HexDefence; Image courtesy of Balmoral

Preliminary work on the Balmoral HexDefence system was based on existing VIV suppression products used widely by the oil and gas sector. Research considered a scaled variant to investigate scour evaluation on downstream flow and the effect of accelerated currents around the monopile. Final prototype testing was completed at a national hydrodynamic laboratory.

The company says that, following positive discussions with leading wind farm developers and industry bodies, it has been encouraged to bring the product to market as soon as possible.

“We believe the system can save wind farm developers around 70% in installation costs when compared to traditional rock dumping methods”, Fraser Milne said.

“With the exponential growth of offshore wind worldwide we believe Balmoral HexDefence can be a key financial enabler and a critical infrastructural element of future offshore fixed wind farms”.