Directory/Stem PowerTrack Optimizer
Needs review
Active
Software platform

Stem PowerTrack Optimizer

Former Athena platform for AI-driven clean energy optimization

HQ: San Francisco, CA 5 states served Since 2009Website
Source-reported capacity
1.2 GW
Managed portfolio
Connected assets
1.1K
Devices & sites
States served
5
Service footprint
Markets
3
CAISO · ISO-NE · NYISO

Overview

About this program

Stem owns and operates commercial behind-the-meter battery systems optimized in real time by PowerTrack Optimizer, formerly known as Athena. The combined fleet provides demand charge management for hosts plus wholesale market participation in CAISO, ISO-NE, and NYISO.

Technologies

Technology breakdown

Battery Storage

Behind-the-meter and front-of-the-meter batteries dispatched for capacity and ancillary services.

Service area

Operating in 5 states

California
New York
Massachusetts
New Jersey
Hawaii

Wholesale markets

CAISO
ISO-NE
NYISO

Programs & Partnerships

Programs and key partners

Programs & offerings

Athena DSGS

California Demand Side Grid Support participation.

ISO-NE Forward Capacity

Wholesale capacity bids from MA + RI fleet.

Partners

PG&E SCE National Grid

Track record

Performance highlights

  1. 1

    1+ GWh of storage under contract

  2. 2

    AI-optimized dispatch with 99.5% uptime

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