This paper investigates the possibilities of integrating oil and gas platforms and offshore wind power to the onshore power grid. The main motivation for this proposal is to reduce the large greenhouse gas emissions associated with onsite power generation on traditional oil and gas platforms and to improve the economy of offshore wind projects. The feasibility of a hypothetical power system in the North Sea consisting of five oil and gas platforms and one offshore wind power plant with a common connection to the onshore power grid is studied. This combined grid integration concept has not been given much attention in similar previous publications. The connection to the onshore grid is realized through a high-voltage direct current transmission system based on voltage source converter technology. A dynamic simulation model of the system and a control system are presented, and simulations are performed, using SimPowerSystems in MATLAB/Simulink, on system disturbances that are thought to be critical for the operation of the system. The simulation cases represent large disturbances that the system should be designed to withstand. It was concluded that the system handles variations in the load very well and that the system configuration studied in this paper is regarded as a feasible way of integrating oil and gas platforms and offshore wind power to the onshore grid.