How big is Stony Brook?

Stony Brook has a reported capacity of 537.5 MW. Source: EIA Form 860M.

What kind of plant is Stony Brook?

Stony Brook is a Natural Gas Fired Combined Cycle facility in Hampden County, MA, participating in the ISO-NE market.

Where is Stony Brook located?

Stony Brook is in Hampden County, MA, inside the ISO-NE balancing area.

Who operates Stony Brook?

Stony Brook is operated by Massachusetts Mun Wholes Electric Co according to the EIA generator inventory. Reporting membership does not by itself establish ultimate ownership.

How much electricity does Stony Brook generate?

Stony Brook reported 165.5 GWh over the twelve months to 2026-04. Figures are net generation as filed to EIA-923.

How does Stony Brook compare to other plants?

By capacity, Stony Brook ranks #20 of 705 operating plants of the same technology nationally. It ranks #2 of 16 in MA.

Ask the Grid

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Stony Brook

Massachusetts Municipal Wholesale Electric CoHampden CountyISONE

Stony Brook Energy Center, listed by EIA as Stony Brook, is a petroleum- and natural-gas-capable generating site in Hampden County, Massachusetts, associated with ISO New England. The EIA plant baseline lists 537.5 MW of nameplate capacity. Massachusetts Municipal Wholesale Electric Company lists a 354-MW intermediate unit and a 172-MW peaking unit, for 526 MW of named-unit capacity. The page keeps the EIA plant baseline and the operator's listed unit totals separate.

Stony Brook — 538 MW oil plant, Hampden County, MA · Ask the Grid

Overview

Nameplate capacity: 537.5 MW
Canonical EIA plant baseline.
Registry anchor: Plant 6081
plant-6081

Structured profile

Technology: Natural Gas Fired Combined Cycle
Operator: Massachusetts Municipal Wholesale Electric Co

Related assets

Similar plants ranked by technology, capacity, and distance.

Montville Station

Petroleum · 489.9 MW

New London County

Same typeComparable scale57 mi away

Compare with this plant

New Haven Steam

Petroleum · 641.5 MW

New Haven County

Same typeComparable scale66 mi away

Compare with this plant

Units and generators

Operating generator records and technology attributes reported through EIA-860.

Generator	Capacity	Technology	Operation	Status
1	85 MW 65 MW summer	Petroleum Liquids Disillate Fuel Oil · GT	Nov 1982	Operating
2	85 MW 65 MW summer	Petroleum Liquids Disillate Fuel Oil · GT	Nov 1982	Operating
5051S	6.9 MW 6.9 MW summer	Solar Photovoltaic Solar · PV	Jun 2018	Operating
BS#1	2 MW 2 MW summer

Performance

Monthly EIA generation history and recent market-resource behavior where linked telemetry is available.

Peer context

Technology capacity: 279.6 MW
National rank: #20
MA rank: #2

Monthly generation

Download CSV

Latest 12 months

165.5 GWh

Reported net generation

Latest report

Apr 2026

EIA-923 monthly filing

2025 capacity factor

2.2%

Using current reported nameplate capacity

Grid and market context

Deterministic links to ERCOT market resources, price records, outage disclosures, queue records, and nearby infrastructure. Candidate joins remain labeled until corroborated.

Nearby substations

HIFLD infrastructure inventory

UNKNOWN133485

IN SERVICE · 345 kV

0.2 km

ORCHARD

Commercial, land, and environmental record

Source-backed project transactions, agreements, land records, permits, and environmental disclosures. Portfolio and adjacent-project facts remain explicitly scoped.

Transactions and agreements

Commercial Operation

1981

Massachusetts Municipal Wholesale Electric Company says the intermediate unit entered operation in 1981.

mmwec.org

Commercial Operation

1982

Massachusetts Municipal Wholesale Electric Company says the peaking unit entered operation in 1982.

mmwec.org

Related parties and identifiers

Parties, market resources, and identifiers tied to this asset, with owner, operator, developer, EPC, compliance provider, and interconnecting entity roles kept separate.

Parties and identifiers

OrganizationRoleBasis

plant:plant-6081Grid selectionCanonical asset page /assets/facilities/stony-brook-energy-center.

Reporting portfolio

EIA reporting entity

Massachusetts Mun Wholes Electric Co

Entity 11806

Operating portfolio

6 plants

1 states

Reported capacity

631.1 MW

Batteries · Natural Gas Fired Combined Cycle · Natural Gas Fired Combustion Turbine

Timeline and sources

Project milestones and public references behind the asset profile.

Project timeline

1981
1981
Intermediate unit entered operationmmwec.org
Massachusetts Municipal Wholesale Electric Company says the intermediate unit entered operation in 1981.
Nov 1981
Nov 1981
Generators enter operation

Largest reported plants in this portfolio
Largest reported plants	Capacity	State
Stony BrookCurrent	537.5 MW	MA
MMWEC Simple Cycle Gas Turbine	65 MW	MA
Berkshire Wind Power Project	19.6 MW	MA
Ashburnham Energy Storage Project	3 MW	MA
SELCO Community Solar	3 MW	MA
Beebe Substation Battery Storage	3 MW	MA

Stony Brook

Stony Brook

Overview

Structured profile

Related assets

Montville Station

New Haven Steam

Units and generators

Performance

Peer context

Monthly generation

Grid and market context

Nearby substations

Commercial, land, and environmental record

Transactions and agreements

Related parties and identifiers

Parties and identifiers

Reporting portfolio

Timeline and sources

Project timeline

Newington

GenConn Middletown LLC

GenConn Devon LLC

William F Wyman Hybrid

Sources

Common questions about Stony Brook

How big is Stony Brook?

What kind of plant is Stony Brook?

Where is Stony Brook located?

Who operates Stony Brook?

How much electricity does Stony Brook generate?

How does Stony Brook compare to other plants?

Co-located assets