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556 kWh

Commercial energy storage systemSungrow

Sungrow STxxxKWH-250UD

556 kWh · 250 kW · Lithium Nickel Manganese Cobalt

UL 9540CEC listed · Jan 21, 2021

Nameplate energy556 kWh
Continuous power250 kW
ChemistryLithium Nickel Manganese Cobalt

Overview

CEC Energy Storage System List

STxxxKWH-250UD: 556 kWh nameplate energy; 250 kW continuous; lithium nickel manganese cobalt.

Capacity & power

CEC Energy Storage System List

Nameplate energy (CEC)556 kWh
Rated power (CEC)250 kW
Max continuous discharge (CEC)250 kW
Full-power discharge timeabout 2.2 h at full power
ChemistryLithium Nickel Manganese Cobalt
Grid connection480 V

Safety listings

CEC Energy Storage System List

UL 9540 (energy storage system)Certified by TUV Rheinland of North America
Certificate date & editionMay 14, 2020 · Ed. 1 : 2016

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)No
UL 1741 SA (Rule 21)Yes
CSIP (IEEE 2030.5)Yes (with conditions)
JA12 declaration (Title 24)No
Monitor Key Data schedulingYes

Questions & answers

How much energy does the Sungrow STxxxKWH-250UD store?

556 kWh nameplate, per the California Energy Commission list.

Is the STxxxKWH-250UD UL 9540 certified?

Yes — the CEC list shows UL 9540 certification (certified by tuv rheinland of north america).

Sources

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