Developers will bid in a three-stage process running until autumn 2020 with seabed rights due to be awarded in 2021.
The Crown Estate confirmed four areas will be available for development: Dogger Bank, the southern North Sea and East Anglia off England’s east coast, the south-east coast, and the Irish Sea and north Wales off the UK mainland’s west coast.
Bidders can identify and propose their own sites within these four areas, with a 3.5GW limit for each area.
The seabed landlord announced a redesigned tender process earlier this year.
It will consist of a pre-qualification stage to assess developer’s technical competence, project-specific financial and technical assessments, and then a multi-cycle bidding process to award projects.
To help incentivise innovation, discounts will also be offered if proposed projects trial new technologies, the Crown Estate said.
Developers will also be allowed to propose hybrid projects, including those that integrate offshore wind with interconnection or other energy generators.
Lease terms have also been extended from 50 years to 60 years — enough for two full project lifecycles, the seabed landlord claimed, "reflecting mature offshore wind technology and operations".
The Crown Estate suggested offshore wind farms resulting from leases awarded in round four could be operational by the late 2020s.
This means these projects could contribute to the UK government’s target of reaching 30GW of installed offshore wind capacity by 2030, up from around 10GW today.
Further capacity will be awarded in the UK’s next contract for differences tender, with results due to be announced tomorrow (20 September).
An additional 7GW of projects would bring the UK’s pipeline of offshore wind farms that are either operational, under construction or planned to more than 43GW, according to trade body RenewableUK.