This dataset represents the construction, installation of equipment and the corresponding decommissioning and disposal required for the grid-connection system of offshore wind power generation, measured in kWh. Offshore booster stations and submarine cable laying are involved, but not onshore central control centers. It is assumed that the construction of the grid-connected system for each wind farm consists mainly of an offshore booster substation and 35 kV submarine cables. During this phase, materials consumed include concrete, reinforcing bars, steel, sacrificial anode aluminum alloy, rubber fenders, etc. The main energy consumption includes diesel fuel used for construction and installation. During the decommissioning and disposal stage of the facility and equipment, a 90% recycling rate is applied for metallic materials such as rebar, steel, iron, aluminum, copper, and electronic components. Resins, rubber, plastics and other materials are disposed of by incineration and other materials by landfill. Data are mainly from public literature and empirical data.