Life Cycle Assessment of Large Wind Turbines in the US: A Texas Case Study

摘要

The overall goal of this study was to conduct the first comprehensive life cycle assessment (LCA) for large onshore wind turbines in the US, including all life cycle phases and multiple impact categories (environmental, human health, resource consumption). Although comprehensive LCAs have been conducted for large wind turbines in Europe, none has been conducted for the US, where different transport distances, vehicle emission standards, and waste disposal practices will affect LCA impacts. This study was conducted for Gamesa 2-MW wind turbines located near Abilene, Texas. SimaPro8 software was used for modeling, according to ISO 14040 standards. The manufacturing phase contributed the most impacts. >6% for all impact categories, followed by installation. The greatest impacts were due to steel production for the turbine tower; hence, alternative materials and methods of manufacturing should be explored for the tower. followed by installation. Even though maintenance was treated comprehensively, the operation and maintenance phase ranked third. Despite the inclusion of overseas transport, transportation ranked fourth. End-of-life ranked last, which means that the disposal method (landfilling or combustion) for turbine parts which are not recycled makes little difference in terms of the overall turbine life cycle. For 20-, 25-, and 30-year lifetimes, the turbines produced 3.4,. 4.2, and 5.1 times more energy than they consumed, respectively. The best-case wind speed recommended by the manufacturer, 8 m/s, overestimated electricity generation by a factor of 2.3 compared to using the wind rose at the farm site. Site-specific information should therefore be used in evaluating the potential for electricity production.