Comparative life cycle assessment of copper, zinc, and lead in offshore wind renewable energy systems: Computing the environmental trade-off for UK’s energy transition

The expansion of offshore wind energy in the UK is essential for achieving net-zero emissions. However, this transition also necessitates a thorough examination of its potential environmental drawbacks. A key area of concern is the use of critical materials and rare earth elements. This paper presents a cradle-to-grave life cycle assessment (LCA) evaluating the environmental impacts associated with the use of three metals—copper, zinc, and lead—across three offshore wind turbine technologies; Direct Drive Synchronous Generator (DDSG), Direct Drive Permanent Magnet Synchronous Generator (DDPMSG), and Doubly-Fed Induction Generator (DFIG). The study quantifies the environmental burdens linked to each metal’s deployment, presents sensitivity analyses based on variations in manufacturing efficiency, and assesses the environmental trade-offs of fossil fuel displacement under three boundary displacement strategies. Results indicate that copper imposes the highest environmental burden, with terrestrial ecotoxicity approximately 1900% greater than that of zinc, while lead exhibits the lowest impacts across all categories. Sensitivity analysis reveals that a 10% improvement in manufacturing efficiency could lead to a corresponding 10% reduction in the Global Warming Potential (GWP) of copper by 2050. Additionally, fossil fuel displacement analysis shows substantial GWP reductions when offshore wind energy replaces natural gas—up to a 2049% decrease under a 100% displacement scenario.