When you divide the total emissions associated with a wind turbine by the amount of electricity it will produce in its lifetime, it works out at about 6 g of carbon dioxide for every kilowatt-hour (kWh) of electricity.1

By comparison, power generation based on fossil fuels involves burning more coal, oil or gas for every kWh of electricity, on top of the one-off carbon emissions from construction and decommissioning. For coal, this adds up to approximately 900 g per kWh.

https://orsted.com/en/insights/the-fact-file/what-is-the-carbon-footprint-of-offshore-wind