Tucson Electric Power (TEP) plans to build a 200 MW battery energy storage system (BESS) – the Roadrunner Reserve system – in southeast Tucson next to a TEP substation to help meet the everyday energy needs of customers for abundant, low-cost solar energy.
The system will be able to store 800 MW hours of energy, enough to serve approximately 42,000 homes for four hours at full capacity, and is scheduled to initiate operations in the summer of 2025. The system will be owned and operated by TEP, while Scottsdale-based DEPCOM Power will design and build it.
The system will use lithium iron phosphate battery units, a newer technology offering longer life and safer operations as compared to other types of battery systems. TEP expects to charge the grid-connected battery in the morning and early afternoon and deliver stored energy later in the day when energy use by customers is highest.
“Roadrunner Reserve will help us maintain reliability as we ambitiously but responsibly expand our community’s renewable resources,” said Susan Gray, TEP’s President and CEO. “This new system will be particularly important in helping us satisfy peak energy needs during the summer.”
The system supports TEP’s 2020 Integrated Resource Plan (IRP) to reduce carbon emissions by 80% and add up to 1,400 MW of energy storage by 2035. TEP plans to file its next IRP on November 1, 2023.
Roadrunner Reserve will build on new additions of renewable resources, such as:
- The 250 MW Oso Grande Wind Project in Roswell, New Mexico, generating enough energy to serve the annual electric needs of about 100,000 homes
- The Wilmot Energy Center, which includes a 100 MW solar array and a 30 MW BESS south of Tucson International Airport, owned and operated by NextEra
- The 99 MW Borderlands Wind Project by NextEra, 100 miles south of Gallup, New Mexico, including 34 turbines to produce enough power to serve about 26,000 homes every year
- The 12.5 MW Raptor Ridge solar system near Interstate 10 and Valencia Road producing enough power to meet the annual electric needs of about 2,500 homes and providing power for homeowners and renters participating in TEP’s GoSolar Home program