This dataset represents the average power generation situation of offshore wind power in the Hainan region of, China, including processes such as oil for wind turbine maintenance and equipment replacement. The offshore wind power technology here uses wind turbines of average scale, and the technical details can be referred to the turbine production dataset. The on-grid electricity of the turbines is determined according to the local grid-connected installed capacity and utilization hours. The wind farm life is set according to official specification standards, namely the technical service life of onshore wind farms is 20 years and that of offshore wind farms is 25 years. The data are mainly sourced from official statistics and public literature.