At the recent 2021 China Wind Power exhibition, DNV awarded an A-Design statement of compliance for insert root to Chinese rotor blade manufacturer LZ Blades. This is the first insert root statement DNV has issued with a partial reduction factor for manufacturing effects of γm3 =1.0.
This is an important milestone for the entire industry and allows LZ Blades to produce a more efficient and cost-effective structure. In addition, quantifying the effect of manufacturing tolerance enables LZ Blades to improve the manufacturing quality without increasing manufacturing costs.
DNV predicts that by 2050, wind will provide 50% of electricity in Europe, 44% in North America and more than 30% of electricity in Greater China, Latin America and South East Asia, says Kim Sandgaard-Mørk, Executive Vice President for Renewables Certification at DNV. “It is essential that we lower the levelized cost of energy (LCOE), making wind energy one of the most economical source of energy generation. We are happy to see that manufacturers like LZ Blade are introducing optimized designs to help achieve this target.”
“During the cooperation with DNV in the blade insert root certification project, LZ Blades has explored the path and accumulated valuable experience in blade subcomponents testing certification process. It also laid a good foundation for the full implementation of IEC’s new blade design standard. LZ Blades will further increase research and investments in blade subcomponent testing technology, continue to optimize blade design, and simultaneously achieve the goal of blade weight and cost reduction and reliability improvement.” Said Liu, Weisheng, the deputy General Manager of LZ Blades.
This milestone could be reached thanks to two industry standards (IEC 61400-5 and DNV-ST-0376) ) which have been published to meet the challenges of the modern blade technological advancements. These standards account for different analysis methods, implement additional validations and focus on the effect of manufacturing tolerances on the design strength. These innovations increase the flexibility and the reliability of blade designs.