Happy Hollow CSG Hybrid
Solar power plant · Worcester County, Massachusetts
Details
- Primary fuel
- Solar
- Technology
- Solar Photovoltaic
- Operator
- REA Investments, LLC
- County
- Worcester County
- Generating units
- 2
- Share of state capacity
- 0.06%
- Rank among solar plants in Massachusetts
- #18 of 531
- EIA plant code
- 62652
Generating units
| Unit | Technology | Nameplate | Summer | Online | Status |
|---|---|---|---|---|---|
| HHPV | Solar Photovoltaic | 5.0 MW | 5.0 MW | 2019 | Operating |
| HHESS | Batteries | 3.3 MW | 3.3 MW | 2019 | 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 Massachusetts
| Adams Grove Solar | Solar | 8.3 MW |
| Clark Road Solar 1, LLC | Solar | 8.3 MW |
| Randall Solar Project Hybrid | Solar | 8.3 MW |
| Williamsville Hybrid CSG | Solar | 8.3 MW |
About this data
From EIA’s inventory of operable generators, May 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 8.3 MW solar plant and a 8.3 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 Massachusetts power plants · What Massachusetts actually generates