Wind energy production in cold climates
Anti-icing technology enables continuous and safe wind energy production even in harsh winter conditions
In order to meet the renewable energy targets by 2020, the aim is to increase the share of wind energy in Finland from 0,3 percent to 6 percent. There is a growing interest from wind farm developers to harvest wind energy in areas of favourable wind conditions that have yet been unexplored due to high risks imposed by local cold weather conditions.
Anti-icing for wind turbine rotor blades
VTT has developed a technology for a blade heating system for wind turbine rotor blades. The basic principle of the system is electro-thermal heating using electrically conductive fibre mats that are integrated in the rotor blade. Because of a smart control system the blade heating is able to prevent ice from building up on the critical parts of the blades. Whereas most de-icing (ice removal) systems would require the wind turbine to be stopped first before being activated, the VTT ice prevention system, or anti-icing system, is able to work during normal operation of the turbine.
Atmospheric icing and cold climate have several detrimental effects on the performance of a wind turbine. The main problem is the ice accumulation on wind turbine blades and on the instruments of the turbine. The ice on the blades reduces their aerodynamic efficiency and can cause power losses as well as an aerodynamic imbalance of the rotor that could ultimately lead to a forced turbine stop. Ice on the wind turbine blades is also a safety risk to both humans and structures. To avoid any risks, in some countries turbines need to be shut down when encountering icing conditions, which leads to production losses. All in all, icing reduces the economy of wind energy production.
The VTT anti-icing system has been installed in more than 40 wind turbines in 600 kW to 3 MW range in Finland and abroad. Its reliability has been proven in over 200 heating seasons. The system consumes heating energy less than two percent of the wind turbine’s annual energy output. Compared to the possible 10 percent loss of energy production due to icing of the blades, the value gained is great.