Offering a total solution for everything from foundation to rotor tip allows Sika to keep pace with the ever-increasing demands of the wind market.

For over 100 years now, Sika has been at the forefront of providing solutions in the areas of sealing, bonding, damping, protecting and reinforcing. Sika is a globally integrated company supplying speciality chemicals and application knowledge, with more than 120 production and marketing subsidiaries in 76 countries. It is therefore no coincidence that today so many of the world’s leading wind turbine producers rely on Sika, with over 25% of the total accumulated global wind power in operation today bonded with Sika products.

Since the development of the first utility-scale wind turbines in the early 1990s, Sika has been supplying solutions for blade manufacturing. From that point, there has been an exponential increase in turbine size and blade length, and Sika’s solutions continue to evolve to meet these needs.

The two fundamentally different blade design concepts in the market have led to mainly epoxy and polyurethane adhesives being used to meet the design demands. Using experience gained from developments in the automotive market, Sika has adapted these to the wind market requirements and has specifically developed toughened epoxy formulations and GL-approved polyurethane adhesives for blade bonding to reinforce its existing range of high-performance epoxy and polyurethane adhesives.

Additionally, Sika offers a range of resins, model boards, pastes and gel coats for mould and model-making as well as GL-approved high-performance infusion resins for blade and part manufacture. The increasing hub height needed for larger turbines has led to higher-performance foundations and hybrid towers to be constructed. For concrete towers and foundations, Sika has developed super plasticisers to improve strength and casting, as well as epoxy adhesives for presetting concrete elements and fast- strength-gain grouts for sealing the vertical joints in the concrete tower sections.

Wind turbines operate in some of the harshest working environments possible. Sika has formulated corrosion protection coating systems for steel tower sections that cover the full range of defined corrosion categories to protect onshore and offshore steel towers and foundations.

Similarly, the cast iron parts of the hub, generator and gearbox are also protected using Sika’s protective coating systems.

It is essential to protect sensitive electrical equipment housed in the nacelle from loss and damage caused by water ingress. Sika has pioneered the development of hybrid sealant/adhesives selected for their UV and weather-resistant characteristics, and proven through their in-service performance over many years. To ensure the long-term performance of the blades, Sika has developed a range of surface-finishing and repair products to allow rapid and reliable repairs to wind turbine blades to minimise downtime and maximise generation efficiency.

Demands to reduce the cost of energy from wind power will largely shape the way the market develops. More powerful turbines to maximise the generation potential per site will place increasing demands on the materials used to withstand the extra loads. With onshore and near-coast shallow-water sites diminishing, more challenging sites will also add further complexity.

As the rate of turbine changes stabilizers, repair and maintenance will become more important to maximise the service life of wind turbines.

The remotest wind farm in the world is also Germany’s first commercial wind farm – Bard Offshore 1, located 125 km off the German coast in international waters. This high-sea wind power plant with 80 windmills has a nominal capacity of 400 MW, which is enough to cover the energy requirements of about 400 000 four-person households. The energy produced is transported through a 125-km long direct current sea cable to the mainland and then another 75 km inland.