Circular Economy and Autonomous Remanufacturing for End-of-Life Offshore Wind Turbines

Offshore wind energy is considered as one of the fastest growing sustainable energy sources in the world. Offshore wind turbines (OWTs) are the most common technology used to harness wind power at sea for conversion to electrical energy. OWTs are often designed for a lifespan of 25 to 30 years, with a possible extension of up to 5 years. Most of the OWTs that were installed in the 1990s and early 2000s have reached, or are approaching, the end of their service lives. This has resulted in increasing concerns about how the large quantities of materials extracted from end-of-life OWTs can be best utilized. "Circular economy" is a new area of research that has recently attracted considerable interest from the offshore wind energy community. This paper aims to present an analysis of the technological, economic, environmental, regulatory, policymaking, cultural, and social challenges confronting the offshore wind energy industry with respect to end-of-life management, including reusing, retrofitting, recycling, remanufacturing, and repowering of OWTs, to support the transition toward circular economy. We then outline some of the business opportunities that Industry 4.0/5.0 and digital technologies can provide for building a more circular and sustainable wind power industry in the future.