As costs decrease, and governments move away from fossil fuels, wind energy is set to be the power of the future. By 2030, turbines are expected to supply 20% of homes in the US with electricity, but these advances come with challenges.
As pressure builds on turbine manufacturers to keep prices down, the need for cost-effective repairs increases. Indeed, operation maintenance now makes up 20-25% of the total ‘levelised cost of energy’ (LCOE) per kilowatt hours.
Long-term benefits
As a business development manager at Sika, Daniel Vogt is keenly aware of how cost pressures can have dire consequences. "What Sika has found in the past is that service teams sometimes use products that are not necessarily specifically designed to repair turbines," he says. "They buy products from the DIY store and believe that they can help fix a turbine in the long term."
Of course, using repair filler originally meant for the car bodywork might make sense at the time, but it is not a good idea.
"What happens then is that these repairs – using products that are not suitable – have to be redone after a short period in service which is false economy," notes Vogt.
Easy does it
Sika works hard to keep quality up and costs down by giving customers a range of high-durability repair products. "Sika has products used in crack repair for foundations, when you have grouting materials that crack during the life of the turbine," he reveals. "The company also has products to repair corrosion in metal towers quickly and reliably."
Blades – Vogt’s own speciality – are not forgotten, either. A range of Sika products can quickly get turbines spinning again if they are hit by lightning or suffering from composite damage. "Sika has repair resins in smart packaging, and has fillers," Vogt says.
This reference to smart packaging is not an accident. With workers fixing turbines from access platforms, or even hanging from ropes, ease of use is crucial.
"We offer smart packaging so that staff do not have to mix two component materials out of larger containers," Vogt explains.
"We have developed ‘mix packs’, whereby components are premeasured in the right quantities, and operators do not need a volumetric measurement to mix in the right ratio. This avoids failures or misuse of the material, and ensures the quality of the final repair."
Stick together
Sika’s novel range of adhesives also helps make the repair process easy. SikaPower-1200 is a toughened structural bonding adhesive for repairing damage on blades, crucial whenever there is damage on the leading edge of a blade, for example.
Sika has been careful to develop it in conjunction with industry colleagues, Vogt emphasises. "This product has been developed in collaboration with one of the major turbine OEMs to repair turbines to an as-new condition," he says.
"That is another important point: in the end, repairs of damaged areas need to have the same strength, and the same durability, as the original material used to build the blade."
Concrete plans
This technical know-how is bolstered by excellent customer service. "A big benefit of Sika is that it is a huge company, with over 18,000 people working in more than 100 countries, so it has local knowledge, worldwide," Vogt explains. "Nevertheless, Sika has a strong local presence in case repairs need to be done quickly."
All this puts Sika in a strong position as it works to develop future solutions. "Sika is expanding its range, especially in terms of concrete repair," Vogt says, "and will be working for blades on a new leading-edge protection coating system – quite a hot topic."
