How many battery storage projects are planned in Maine?

2, for 15 MW of nameplate capacity. These are generators developers have reported to EIA, not generators that exist.

What do the status letters mean?

EIA files each planned generator under a status: regulatory approvals pending, under construction at or below half complete, under construction more than half complete, construction complete but not yet in commercial operation, or planned but not yet started. Each row shows its own.

Do these projects always get built?

No. EIA keeps a separate Canceled or Postponed sheet, and projects move between the sheets month to month. This page is the Planned sheet for 2026-07 and nothing more.

Planned battery storage projects in Maine

What EIA-860M's Planned sheet says is coming in Maine: 2 battery storage projects totalling 15 MW, each with the in-service year its developer reported and the construction status EIA records. A planned project is not a built one.

As of 2026-07 (inventory dated 2026-07-31) · EIA-860M Preliminary Monthly Electric Generator Inventory · eia.gov/…/july_generator2026.xlsx · eia.gov/…/eia860m

Planned projects: 2; 2 generating units
Proposed capacity: 15 MW
Earliest in-service year: 2027
Latest in-service year: 2027

Map of planned battery storage projects in Maine

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List of planned battery storage projects in Maine

Planned battery storage projects in Maine

South Portland ESS, LLCBatteries	South Portland ESS, LLC	Cumberland	10	1	2027	Regulatory approvals received. Not under construction
Sanford ESS, LLCBatteries	Sanford ESS, LLC	York	5	1	2027	Regulatory approvals received. Not under construction

Where they are in the build

Regulatory approvals received. Not under construction2

Planned battery storage projects in Maine: FAQ

How many battery storage projects are planned in Maine?: 2, for 15 MW of nameplate capacity. These are generators developers have reported to EIA, not generators that exist.
What do the status letters mean?: EIA files each planned generator under a status: regulatory approvals pending, under construction at or below half complete, under construction more than half complete, construction complete but not yet in commercial operation, or planned but not yet started. Each row shows its own.
Do these projects always get built?: No. EIA keeps a separate Canceled or Postponed sheet, and projects move between the sheets month to month. This page is the Planned sheet for 2026-07 and nothing more.