  The European North Sea has a vast renewable energy potential and can be a
powerhouse for Europe's energy transition. However, currently there is
uncertainty about how much offshore wind energy can be integrated, whether
offshore grids should be meshed and to what extent offshore hydrogen should
play a role. To address these questions, we use the open-source energy system
optimization model PyPSA-Eur to model a European carbon-neutral sector-coupled
energy system in high spatial and temporal resolution. We let the model
endogenously decide how much offshore wind is deployed and which infrastructure
is used to integrate the offshore wind. We find that with point-to-point
connections like we have today, 310 GW offshore wind can be integrated in the
North Sea. However, if we allow meshed networks and hydrogen, we find that this
can be raised to 420 GW with cost savings up to 15 billion euros per year.
Furthermore, we only observe significant amounts of up to 75 GW of floating
wind turbines in the North Sea if we have offshore hydrogen production.
Generally, the model opts for offshore wind integration through a mix of both
electricity and hydrogen infrastructure. However, the bulk of the offshore
energy is transported as hydrogen, which is twice as much as the amount
transported as electricity. Moreover, we find that the offshore power network
is mainly used for offshore wind integration, with only a small portion used
for inter-country transmission.
