Mammoth Plains Energy Storage

A 150 MW battery storage project in Dewey County, Oklahoma. Mammoth Plains Energy Storage has asked to connect to the grid or filed for its first approvals; nothing on record yet commits money to it. Public records name Mammoth Plains Energy Storage, LLC as its developer. No public record read so far names its builder.

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The record

What the public record says about Mammoth Plains Energy Storage, as of 24 Oct 2026.

Stage	Queued
Construction start	Q4 2026 estimate
Size	150 MW
Location	Dewey County, Oklahoma (to about 10 km)
Developer	Mammoth Plains Energy Storage, LLC
Grid operator	—
Builder (EPC)	Not named yet
Trade subcontractors	in the app
People to call	in the app
Phase windows	in the app

Every fact in the app links to the public record behind it, with how many records agree and whether it is confirmed, reported or an estimate. What the terms mean.

What happened

Each change dated by the scene or the document, newest first.

No change on record since Groundtrace started tracking it.

Who was named on it, and when, is in the app.

Also in Dewey County

Project	Stage	Size
Mammoth Plains Energy Storage IIBattery storage	Queued	101 MW
Unnamed 42 MW wind projectOnshore wind	Queued	42 MW
Crossroads Wind FarmOnshore wind	Operating	228 MW
Mammoth PlainsOnshore wind	Operating	226 MW
Seiling Wind IOnshore wind	Operating	199 MW
Taloga WindOnshore wind	Operating	130 MW

Battery storage in Oklahoma Every industry in Oklahoma How to tell a project is about to break ground

Questions

Mammoth Plains Energy Storage, in short.

Where is Mammoth Plains Energy Storage?

Mammoth Plains Energy Storage is a 150 MW battery storage project in Dewey County, Oklahoma. The public page places it to within about ten kilometres; the precise location is in the subscriber record.

When does construction start on Mammoth Plains Energy Storage?

Groundtrace estimates construction starts in the fourth quarter of 2026. This is an estimate from the project's filings, not a date any record states; the exact date and the record behind it are in the subscriber record.

Who is developing Mammoth Plains Energy Storage?

Mammoth Plains Energy Storage, LLC, as the public record names it.

Who is building Mammoth Plains Energy Storage?

No public record read so far names a builder for Mammoth Plains Energy Storage. Groundtrace leaves the field empty rather than guess, and fills it when a permit, a filing or the builder's own page names one.