There’s a constant debate about the effectiveness of de-icing systems. Now Sweden’s biggest wind turbine owner is asking for performance guarantees.
Owners of wind turbines want high productivity in order to obtain the required return on investment, but icing can easily lead to a 10 % loss of production, which can dramatically affect profits.
”We need better assurances from the manufacturers. Today it is difficult to know what performance to expect from the de/anti-icing systems on the market, ” says Daniel Gustafsson, project leader at Sweden’s largest utility, Vattenfall.
What form could a performance guarantee take?
”We could have an icing loss guarantee that e.g. limits icing-related production loss to 2 %.”
”A second solution might be a system performance guarantee, where the manufacturer guarantees that the de-icing system will keep the turbine operational, provided that e.g. wind speed does not exceed 20 m/s or the ambient temperature does not fall below -15 °C.”
”The third and least comprehensive guarantee would be a functional warranty, where the manufacturer only promises to deliver a certain amount of heating power to the blades.”
How have manufacturers reacted to this demand?
”They understand our point of view, but the de/anti-icing systems are new and lack a sufficient track record. Site conditions also play a large role in how well they work. Additionally, any warranty offered by turbine suppliers exposes them to icing-related risk.”
Is there a lack of knowledge regarding how de-icing systems work?
”Yes, too often we only talk about the heating system, but an anti/de-icing system also consists of ice detection and a control system. These three features have to be fully integrated, and a lot of work remains to be done in optimizing control systems.”
Apart from guarantees – is there anything else that would make it easier for owners to invest in de-icing systems?
”We need more data from the manufacturers, so that we can evaluate and compare different systems. There should also be third party evaluations of each system.”
Daniel Gustafsson is a project manager at Vattenfall Windpower and is currently developing new wind farms in northern Sweden. He is also active in Vattenfall’s internal ice-research program.
Vattenfall is one of Sweden’s largest owners of wind turbines, with more than 100 units.