Under the Electric Reliability Council of Texas’ (ERCOT) new winter readiness efforts, generators across the state were asked to complete certification of compliance status of generation units and transmission systems by December 1, 2021. As part of our formal response to ERCOT on November 30, 2021, CPS Energy reported all transmission systems and 12 generation units (11 thermal units and 1 battery storage site) as fully compliant. All transmission system readiness requirements are also complete.
As part of our ongoing reliability and resiliency efforts, CPS Energy modified power plant outage schedules to ensure there are no planned outages in January or February or during the summer peak months. To ensure our highest energy demand months are preserved, we will be completing some of our winter preparedness maintenance outages during the month of December. We expect that all planned outage work currently underway will be completed by the end of the calendar year.
Our work continues to protect customers through this winter and beyond. We reported to ERCOT that 11 generation units will remain in non-compliance status until planned maintenance outages are complete, while one unit will remain in a forced outage until early January 2022 to address items discovered during a planned inspection in mid-October 2021. As generating units come back into service, we will formally notify ERCOT and will continue to share updates with our community.
The certification of compliance is a separate effort from weatherization of our generation units. Weatherization initiatives to protect the plants, pipes and other critical equipment from freezing weather are complete. More than 100 temporary structures have been built to protect critical equipment along with the inclusion of a variety of other measures such as the placement of additional heaters, protective barriers and new measures totaling $2 million since February 2021. The added protection strengthens nearly $20 million in improvements following extreme winter weather in 2011.