Abstract
As the global fleet of wind power projects continues to grow and age, and with significant improvements to turbine technology in the past decade, repowering is increasingly prevalent. The current trend favors partial repowering, in which the existing wind turbine foundations, wind turbine towers, and electrical balance-of-plant systems are left in place; and wind turbine blades are replaced with new, longer blades, and at least some portion of the wind turbine drivetrain is upgraded.

Partial wind project repowering enables owners to generate more energy from their sites, extend the life and improve the availability of their projects, and take advantage of extended renewable energy production tax credits. Partial repowering was implemented at dozens of sites in 2017 and 2018, and is expected to be widely implemented in 2019 and 2020.

Sargent & Lundy has recent experience with 35 repowered wind projects, involving more than 2,600 wind turbines; we have a carefully considered methodology founded on both our thousands of hours of analysis across our recent projects for repowering wind turbines as well as our industry-leading depth of structural and electrical engineering experience.

Sargent & Lundy is at the forefront of providing engineering and consulting services for these projects and is pleased to release the following white paper that highlights best practices, common issues, and insights we have identified during recent wind repowering efforts.

Authors: Brian Connaghan, Eric DeCristofaro, Eric Soderlund, Matthew Thibodeau, and Xuan Wang – Sargent & Lundy