Wind power or wind energy is the use of wind turbines to generate electricity. A wind turbine is a device that converts the wind's kinetic energy into electrical energy. The amount of power that can be harvested from wind depends on the size of the turbine and the length of its blades. The output is proportional to the dimensions of the rotor and to the cube of the wind speed. Theoretically, when wind speed doubles, wind power potential increases by a factor of eight. Offshore wind farms with fixed foundations are the most common type of installation and by far the most mature of the offshore renewables technologies. Such turbines, as a result of R&D, are being routinely deployed in water depths of up to 40 metres, and in some cases up to 60 metres, and at up to 80 kilometres’ distance from shore. A variety of fixed offshore wind turbines have been developed over time, with the most common types being gravity-based foundations, monopile foundations, tripod foundations and jacket foundations. Offshore wind is in a category of its own, as the only variable baseload power generation technology. New offshore wind projects have capacity factors of 40%-50%, as larger turbines and other technology improvements are helping to make the most of available wind resources. At these levels, offshore wind matches the capacity factors of efficient gas-fired power plants, coal-fired power plants in some regions, exceeds those of onshore wind and is about double those of solar PV. Europe is a leader in offshore wind technology, but capacity is set to grow around the world. Global installed capacity of onshore wind in 2020 was about 35 GW. To attain the 8 000 TWh required in 2030 under the Net Zero Emissions by 2050 Scenario of the IEA, it iso necessary to raise annual capacity additions to 80 GW of offshore wind.