GL Renewables Certification (GL) has issued an update to its technical note ‘Certification of Wind Turbines for Extreme Temperatures’ in order to ensure that wind turbines can operate in cold climates.
Building on previous revisions and the knowledge gained through both project experience and cold-chamber testing, and also taking into account the new GL Guideline for the Certification of Wind Turbines 2010, this is the fourth revision of the note since its introduction. GL first issued the note in 2005 and has been continually revising and updating it ever since to reflect advances in technology and growing expertise gained through the continued testing of turbines in extreme temperatures, the organization explains.
The latest technical note provides information on load assumptions, safety and control systems, manuals, rotor blades, nacelle covers and spinners, machinery components, strength verification, building structures, and electrical installations.
A location is considered a "cold climate" site if minimum temperatures of below -20 degrees C have been observed during long-term measurements on an average of more than nine days a year, for a minimum of one hour. If a site fulfils these conditions, cold-climate requirements should be considered in the design of the turbine.