CPS Energy Calaveras Power Station

The CPS Energy Calaveras Power Station, home to four coal-fired units, is located southeast of San Antonio in Bexar County, Texas.  The coal units are members of a diverse CPS Energy generation fleet, which also consist of nuclear, gas, solar and wind.

CCR Compliance

Since the early 1990s, CPS Energy has recycled more than seven million tons of coal combustion residuals (CCRs), or coal ash. Recycling coal ash to create concrete significantly reduces the amount of cement that must be manufactured, decreasing greenhouse gas emissions generated during the cement production process.

CPS Energy recognizes and supports responsible handling of CCRs and intends to meet or exceed the requirements of the CCR rules. If you have questions or desire further information, please provide your information in the link provided here. 

The six units relevant to the CCR rules are the following:

• SRH Pond
• North Bottom Ash Pond
• South Bottom Ash Pond
• Fly Ash Landfill
• Evaporation Pond
• Plant Drains Pond

ELG Compliance

The Effluent Limitation Guidelines (ELG) rule sets federal limits on the discharge of flue-gas desulfurization (FGD), bottom ash transport water (BAT) and combustion residual leachate (CRL).  To comply with the ELG rule, CPS Energy filed a Notice of Planned Participation (NOPP) for the Voluntary Incentive Program (VIP) treatment path with the Texas Commission on Environmental Quality (TCEQ) during a wastewater permit renewal in 2018 for Calaveras Power Station.  The VIP treatment path places stringent limits on the wastewater discharge from coal-fired power plants or allows for zero liquid discharge (ZLD) treatment options.  CPS Energy opted to pursue ZLD treatment with either the cessation of coal combustion or the cessation of wastewater discharge by December 31^st, 2028. 

In December 2025, CPS Energy officially filed a NOPP with the TCEQ to cease coal combustion at J. K. Spruce 1 and J. K. Spruce 2 units located at Calaveras Power Station by December 31, 2028.