Electricity generation is the process of generating electric power, expressed in terms of gigawatt-hours. Wind energy is harnessed directly from the flow of air through the use of onshore and offshore wind energy technologies. Wind energy is harnessed directly from the flow of air through the use of onshore and offshore wind energy technologies.Onshore wind power refers to turbines that are located on land and use wind to generate electricity. Offshore wind power is the generation of electricity through wind farms in bodies of water, usually at sea.