Cali-Graf in Southern California

For pros Sign in

133 kWh

Commercial energy storage systemFortress Power

Fortress Power MINI-60-xxx-xxx-480

133 kWh · 60 kW · Lithium Ion · direct PV input

UL 9540UL 1741 SBCEC listed · Apr 11, 2024

Nameplate energy133 kWh
Continuous power60 kW
Round trip (AC)80%
ChemistryLithium Ion

Overview

CEC Energy Storage System List

MINI-60-xxx-xxx-480: 133 kWh nameplate energy; 60 kW continuous; lithium ion; accepts solar panels directly (DC-coupled).

Capacity & power

CEC Energy Storage System List

Nameplate energy (CEC)133 kWh
Rated power (CEC)60 kW
Max continuous discharge (CEC)60 kW
Full-power discharge timeabout 2.2 h at full power
Round-trip efficiency (AC-AC)80%
ChemistryLithium Ion
Grid connection480 V

Safety listings

CEC Energy Storage System List

UL 9540 (energy storage system)Certified by Intertek
Certificate date & editionMar 14, 2024 · Ed. 2 : 2020

UL 9540 certifies the whole storage system; UL 9540A is the fire-propagation test that fire codes ask for indoors and near walls.

California grid & code compliance

CEC Energy Storage System List

UL 1741 SB (IEEE 1547-2018)Yes
UL 1741 SA (Rule 21)No
CSIP (IEEE 2030.5)Yes (with conditions)
JA12 declaration (Title 24)Yes
JA12 control strategiesBasic, TOU, Advanced DR
Last CEC updateFeb 21, 2025
Monitor Key Data schedulingYes

Questions & answers

How much energy does the Fortress Power MINI-60-xxx-xxx-480 store?

133 kWh nameplate, per the California Energy Commission list.

Is the MINI-60-xxx-xxx-480 UL 9540 certified?

Yes — the CEC list shows UL 9540 certification (certified by intertek).

Sources

California Energy Commission — Energy Storage System List, data as of Oct 7, 2026. Manufacturer-reported values confirmed by CEC against certificates.