SeaEnergy has stakes in three offshore projects, including the 1.5GW Moray and development. Repsol will now work on this project with partner EDPR.
The deal is subject to SeaEnergy shareholder approval.
SeaEnergy said it will now focus on its existing assets, in particular its offshore renewables marine services business SeaEnergy Marine.
In a statement is said: "The Company believes that a significant opportunity exists as a result of the large numbers of offshore wind turbines expected to be installed in UK and European waters over the coming years."