Environmental Impacts of Global Offshore Wind Energy Development until 2040

Continuous reduction in the levelized cost of energy
is driving
the rapid development of offshore wind energy (OWE). It is thus important
to evaluate, from an environmental perspective, the implications of
expanding OWE capacity on a global scale. Nevertheless, this assessment
must take into account various scenarios for the growth of different
OWE technologies in the near future. To evaluate the environmental
impacts of future OWE development, this paper conducts a prospective
life cycle assessment (LCA) including parameterized supply chains
with high technology resolution. Results show that OWE-related environmental
impacts, including climate change, marine ecotoxicity, marine eutrophication,
and metal depletion, are reduced by ∼20% per MWh from 2020
to 2040 due to various developments including size expansion, lifetime
extension, and technology innovation. At the global scale, 2.6–3.6
Gt CO2 equiv of greenhouse gas emissions are emitted cumulatively
due to OWE deployment from 2020 to 2040. The manufacturing of primary
raw materials, such as steel and fibers, is the dominant contributor
to impacts. Overall, 6–9% of the cumulative OWE-related environmental
impacts could be reduced by end-of-life (EoL) recycling and the substitution
of raw materials.