Callisto II Energy CenterUnder construction
Harris County, Texas · EIA plant ID 68422 · Operator: Callisto II Energy Center LLC
400 MW under construction (Batteries), first expected Nov 2026 · EIA-860M
Nameplate—MWSummer — MW
Generators0in service · 400 MW building
Net generation—GWh12 mo
Capacity factor—not meaningful for storage
Heat rate—thermal plants only
First online—
Capacity factor by year
Net MWh ÷ (summer MW × hours), primary-fuel units. Each year uses that year's EIA-860 ratings; the hollow dot is the latest 12 months.
No capacity factor available.
Heat rate by year
Electric fuel MMBtu × 1000 ÷ net MWh (Btu/kWh, HHV), fossil units only; CT + CA counted as one combined-cycle block.
Heat rate applies to fuel-burning (thermal) units only.
Generators
EIA-860 (annual) with EIA-860M updates through Sep 2026. EIA-923 reports generation by plant, prime mover and fuel, not by unit, so unit-level output isn't shown.
| Gen ID | Technology | Prime mover | Nameplate MW | Summer MW | Online | Status | Planned retirement | OEM / model |
|---|---|---|---|---|---|---|---|---|
| CALII | Batteries | BA | 400 | 400 | planned Nov 2026 | Under construction | — | coming soon |
Owner / operator
Operator: Callisto II Energy Center LLC. Ownership shares by in-service nameplate MW (EIA-860 Schedule 4; units not listed there are wholly owned by the operator).
Nearby plants
Within 80 km.
| Pamela Heights I Energy Center | — | 0 km |
| HO Clarke Generating | 484 MW | 0.1 km |
| Callisto I Energy Center | 223 MW | 0.2 km |
| Friendswood Energy | 265 MW | 0.2 km |
| OTHERTraditionBuffalo | 1 MW | 4.9 km |
| Telview ESS | 10 MW | 8.2 km |