Skip to main content
  • Press Release

UL Grants ERG First Wind Turbine Lifetime Extension Certificate

The move helps advance the ongoing safe operation of clean, sustainable energy generation.

Wind turbines on a treeless hill under a blue sky with billowy clouds

February 2, 2021

Northbrook, Illinois – February 2, 2020 – UL, the leading global safety science leader, announced today that ERG, producers of electricity from clean, renewable and sustainable sources, is the first entity to receive a certificate for UL 4143, the Standard for Wind Turbine Generator Life Time Extension, for an ERG wind farm in Italy.

UL 4143 is a process of assessing lifetime extension for a wind farm through onsite inspection of turbines and blades focused on structural integrity, and an analytical evaluation of the site conditions to determine the remaining useful life for each structural component. The evaluation is done using UL’s aerolastic models with inputs from the plant such as building permits, maintenance and inspection records, SCADA data, power curtailment, type certificates, and more.  The outcome is summarized in a final report defining the remaining useful life (RUL) of the plant and the conditions under which it can be achieved. 

ERG, one of the largest onshore wind energy operators in Europe with a total installed capacity of 1.9 GW, owns a fleet of wind turbines in Italy, France and Germany that are reaching 20 years of operation, the typical design life of a wind turbine. To achieve the UL 4143 Standard certificate, UL performed a number of lifetime assessment and aging plant analyses. ERG’s wind turbines were analyzed to determine the RUL of the operational wind turbines. The structural integrity of the turbines was also confirmed by means of load simulations performed to assess the safety and viability of extending turbine life. Additionally, a risk analysis evaluation and on-site inspection was performed to evaluate potential rising risks connected with the aging turbines.

“Turbines are designed for specific International Electrotechnical Commission wind class conditions based on average wind speed, extreme gusts, and turbulence, and typically for a 20-year expected lifespan. In many cases the actual wind conditions are less aggressive than design conditions, and enough margin exists in the design that the turbine can safely operate well beyond its intended life,” said Michael Brower, vice president in the Renewables division at UL. “The goals for UL are to support the sustainable, safe operation and to help maximize the life and value of their operating wind assets.”

UL holds a leading position in the independent lifetime extension evaluation market having recently surpassed 20 GW assessed around the world for over 9000 turbines, 160 wind turbine models from 27 manufacturers.  

To read more about UL’s Lifetime Extension services, visit  

About UL
UL helps create a better world by applying science to solve safety, security and sustainability challenges. We empower trust by enabling the safe adoption of innovative new products and technologies. Everyone at UL shares a passion to make the world a safer place. All of our work, from independent research and standards development, to testing and certification, to providing analytical and digital solutions, helps improve global well-being. Businesses, industries, governments, regulatory authorities and the public put their trust in us so they can make smarter decisions. To learn more, visit To learn more about our nonprofit activities, visit


Press Contact: