Mitsui Invests $12M In Stem’s Behind-The-Meter Energy Storage

Mitsui, a Japan-based industrial conglomerate, leads a first tranche of $12 million Series C round funding into Stem Inc., a start-up that provides batteries and intelligent software-controlled energy storage. This follows other venture capital investments from Angeleno Group, Iberdrola, GE Ventures, Constellation New Energy, and Total Energy Ventures.

Stem allows businesses to better control electricity costs and demand charge. When electric rates increase, its software switches the building to battery power which were charged when rates were low.

It also sells services to utilities in what is called demand-response—it can tell utilities to switch off its customers in an area to battery power to reduce demand on the grid. Some customers include Southern California Edison and Hawaii Electric.

Stem uses lithium-ion batteries from Panasonic and LG Chem. Third-part finance helps to finance Stem’s installations, running a similar leasing model to SolarCity and Sunrun Inc.

If you want to know more about this and other topics directly from end users of energy storage technologies join us at one of these annual events: The Energy Storage World Forum (Grid Scale Applications), or The Residential Energy Storage Forum, or one of our Training Courses.


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