The power output of wind turbines will vary according to the amount of capacity deployed and the load factor at which these operate (which is dependent on wind speeds). At the end of 2014, 12,987 MW of wind turbine capacity was installed in the UK. During 2014, these turbines operated at a load factor of 30.2 per cent. Taken over the last three years, the load factor was 29.8 per cent.
Source: Tables 3 and 4 in: Renewable energy in 2014, Energy Trends June 2015, available at:
To note, the capacity and load factor figures given above should not be multiplied to give an annual average power output, since not all capacity would have been installed at the beginning of the year.