Wind generators operate at 28 % capacity factor but have only 11 % availability at peak demand due to lower wind output in the summer. (windconcernsontario.ca)
Wind output during the summer months frequently coincides with the afternoon and evening peak demand hours, but it is also an intermittent resource and therefore has a limited ability to provide firm capacity. (eia.gov)
Note also that the southeast does not have installed wind turbines because wind speeds there are not conducive for much wind output. (instituteforenergyresearch.org)