Environmental life cycle assessment of a novel offshore wind energy design project: A United States based case study

Renewable energy resources, particularly offshore wind energy, and their role in combating global climate change have gained significant interest in recent years. Considering the potential life cycle impacts of such systems is essential to support effective policy and decision making. This study used life cycle assessment to compare the environmental sustainability of an offshore wind farm case study employing a novel foundation design to one employing a conventional foundation design. Literature has not yet examined the life cycle environmental sustainability of large-scale United States based facilities using a detailed data inventory from a real case study. The life cycle environmental single score of the novel design was 18% lower than that of the conventional design, highlighting that alternative foundation materials like concrete can help reduce the overall life cycle environmental impact of a large scale offshore wind farm. In general, the proposed novel design is favorable from a life cycle perspective compared to the conventional design, particularly in the impact categories of ecotoxicity, eutrophication, carcinogenics, noncarcinogenics, and respiratory effects. The energy payback time was found to be less than one year for both designs. Additional benefits of the novel design concept include lower costs, easier installation, domestic job opportunities, decreased reliance on foreign supply chains, ability to expand the design to deeper and disaster prone waters globally, and increased support for current political goals. Scenario sensitivity analyses showed that the environmental impact of wind energy systems may decrease with domestic sourcing of foundation materials and foundation reuse after decommissioning.