The database for the evaluation for a turbine’s potential to extend its lifetime can be very different. Site-specific information, turbine-type related experience, accessibility of design documentation are important aspects that may influence the approach. Being aware of this DNV GL has developed different methods in order to provide more guidance on possible approaches for lifetime extension and to offer adequate solutions to operators of single wind turbines as well as of large wind farms or even to manufacturers.
These methods have been implemented in the new service documents DNVGL-ST-0262 ‘Lifetime extension of wind turbines’ and DNVGL-SE-0263 ‘Certification of lifetime extension of wind turbines’. All methods evaluate the suitability of the turbine for the life time extension, and depending on the purpose, they have a different level of detail. The methods ‘simplified approach’, ‘detailed approach’ and ‘probabilistic approach’ consist of an analytical and a practical part. They include quantification of the remaining useful life (“proof of strength and stability”) based on different procedures.
