Optimal Environmental Siting of Future Wind Turbines in the North Sea

Offshore wind energy (OWE) represents a key technology
for achieving
a sustainable energy transition. However, offshore wind farms (OWFs)
can impact the environment via installation, operation, maintenance,
and decommissioning activities together with the raw materials and
energy required for their manufacturing. This study assesses the material
and carbon footprint of potential OWF locations in the North Sea for
various possible future technology developments. We find that better
sitings could save up to ∼0.11 kg (∼65%) of steel, ∼
0.16 g (∼31%) of copper, and ∼6.44 kg (∼26%)
of embodied CO2-eq per MWh of electricity produced compared
to the status quo setups. Nearshore regions of the North Sea, particularly
the eastern and northwestern areas, have the lowest CO2-eq per MWh of electricity produced due to favorable wind resources.
Developing an OWF in the central North Sea requires more copper and
aluminum due to large distances to shore and thus incurs higher embodied
CO2-eq per MWh. These areas also overlap with several protected
areas and thus remain the least favorable for OWE development. The
future emergent OWE technological developments for 2040 such as the
installation of larger turbines with an extended lifetime alone could,
on average, lead to reductions of ∼0.06 kg in steel demand
(∼35%), ∼ 0.15 g in copper demand (∼31%), and
∼10.97 kg of CO2-eq (∼41%) per MWh produced.
Future OWFs incorporating these technological developments, when placed
in the most suitable locations, have the potential to substantially
lower OWF environmental impacts across the full turbine life cycle.