Stephentown Spindle — United States of America

Stephentown Spindle is a 20 MW storage power plant in Massachusetts, United States of America. It is operated by Convergent Energy and Power LP. Based on its capacity (estimated), it can supply roughly 5.0k homes (estimated). It ranks #4791 of 10,884 United States of America power plants by installed capacity. Commissioned in 2011, it is around 15 years old — relatively modern. As a non-combustion source, it has no direct CO₂ emissions from generation. In context, the national grid averages 384 gCO₂/kWh (43.0% low-carbon) (2025).

Plant data: WRI Global Power Plant Database (CC BY 4.0), id USA0057710.

Data provenance

Source of the capacity and fuel values:

capacity: Wikidata P2109; fuel: WRI GPPD

In context: how this plant compares

At 20 MW, Stephentown Spindle is well above the median storage plant in United States of America (4 MW). This facility converts its energy source into electricity for the grid; its capacity, fuel type and location determine its role in the national power mix.

Capacity comparison computed from the WRI Global Power Plant Database; fuel-type context is general engineering background.

Key facts

Share of United States of America storage capacity

2.5% of 815 MW across 104 plants in this dataset

Age among peers

5 of 104 dated storage plants in United States of America are older

Calculated from the capacity and generation records in this dataset (WRI Global Power Plant Database (CC BY 4.0)).

Reported generation trend

Annual generation (GWh), WRI Global Power Plant Database (CC BY 4.0).

Owner

Operated by Convergent Energy and Power LP.

Local climate & thermal context

This storage plant stores and releases electricity (pumped-hydro or batteries) to balance the grid. It sits in a warm-summer humid continental climate (Köppen Dfb) — Northern Hemisphere, latitude 42.6°N — which shapes how much energy it can produce and how its output varies through the year.

Monthly mean temperature

Heating degree-days here run 65% above the median power plant in this dataset — a proxy for how much extra energy heated equipment must replace through its surfaces in winter.

Climate heat-demand index: 85/100 — this site sits in the top third of the power plants we cover by heating degree-days.

Climate normals: WorldClim 2.1 (1970–2000 monthly normals, 10 arc-min, CC BY 4.0); zone: Köppen-Geiger world climate classification (Kottek et al. 2006, 0.5° grid). Degree-days & heat-demand index computed by PowerAtlas — a modelled heat-demand proxy, not a measured site figure.

Site climate & environmental severity

This site sits in a mild atmospheric environment (estimated ISO 9223 class C2 — Low), with thermal cycling the leading environmental stress.

Indicative estimate via the ISO 9223:2012 informative method (atmospheric corrosivity from temperature, time-of-wetness and airborne salinity), using WorldClim climate normals, the Köppen-Geiger class and coast distance. Indicative, not a measured corrosion rate.

How it compares & nearby plants

The #13 largest storage power plant of 104 in United States of America by capacity.

United States of America has 104 storage power plants in this dataset, together about 815 MW of capacity.

Nearby power plants

• Jiminy Peak Wind QF · Wind · 1.5 MW · Massachusetts
• Nexamp Peak CSG · Solar · 2 MW · Massachusetts
• Berkshire Wind Power Project · Wind · 19.6 MW · Massachusetts
• East Acres Solar NG LLC · Solar · 5.8 MW · Massachusetts
• Syncarpha Hancock I CSG · Solar · 2 MW · Massachusetts
• Syncarpha Hancock II CSG · Solar · 2 MW · Massachusetts

Location

Coordinates 42.5565, -73.3775 from WRI Global Power Plant Database (CC BY 4.0). View on OpenStreetMap.

Frequently asked questions