Roadrunner Reserve Phase 2
Battery storage power plant · Pima County, Arizona
Nameplate capacity
200 MW
Rank in Arizona
#58
of 205 plants
In service since
2026
June 2026
Details
- Primary fuel
- Battery storage
- Technology
- Batteries
- Operator
- Tucson Electric Power Co
- County
- Pima County
- Generating units
- 1
- Share of state capacity
- 0.44%
- Rank among battery storage plants in Arizona
- #10 of 26
- EIA plant code
- 68937
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| RDR2 | Batteries | 200 MW | 200 MW | 2026 | Operating |
Nameplate is the maximum rated output; summer capacity is what the unit can reliably deliver on a hot day, which is typically lower.
Similarly sized plants in Arizona
| Flatland Storage | Battery storage | 200 MW |
| Roadrunner Reserve Phase 1 | Battery storage | 200 MW |
| Westwing | Battery storage | 200 MW |
| Wilmot Energy Center II | Solar | 200 MW |
About this data
From EIA’s inventory of operable generators, August 2026 release. Capacity is nameplate — the maximum rated output of the equipment, not what the plant actually generates over a year, which depends on how often it runs. A 200 MW solar plant and a 200 MW nuclear plant have the same entry here and produce very different amounts of electricity.
“In service since” is the earliest in-service date among the units still listed, so a site rebuilt around newer equipment can read as younger than the site itself. All Arizona power plants · What Arizona actually generates