Dong has acquired the entire 4GW Hornsea zone and the project rights to Hornsea Project Two and Three from Smart Wind – a joint venture between Mainstream Renewable Power and Siemens Financial Services.
It follows the developer's acquisition of the 1.2GW Hornsea Project One in February 2015.
Dong will now assume responsibility for the whole Hornsea zone, which lies in the North Sea, between 31 and 190km off the Yorkshire coast, east England.
Covering an area of 4,735 square kilometres, it could host around 4GW of offshore wind capacity.
