To take advantage of better technology and boost capabilities, one of the largest clean energy developers in the United States sought to replace existing turbines with new models. Barr assisted this client by performing a structural assessment for the repowering of a 150-megawatt wind farm.
Barr first conducted a desktop evaluation to determine if the proposed foundations could support the new loads. Additionally, since industry design practices for anchoring turbine towers to their foundations had changes since their original design, we also developed a calculation procedure based on an analogous design formula and our knowledge of historical foundation performance. Based on these evaluations, our determination was that the new specifications could be met.
To validate our initial determination, we selected a subset of foundations at the site for further inspection and testing. Field investigation involved structural health monitoring (SHM) to determine each foundation’s performance while its turbine was operating. We also performed visual inspections and coring inside the foundations to check for cracking or hidden issues.
We determined the foundations at this site could support the new turbines without costly modifications. Our team also developed a foundation risk-management program that consisted of performing SHM on select foundations over specific intervals. These findings and recommendations allowed the client to move ahead with repowering while continuing to produce power for 40,000 households.