Stem’s virtual power plants take heat off Californian grid

By John Parnell
LinkedIn
Twitter
Reddit
Facebook
Email
The CAISO control room in Folsom. Image: CAISO.

Stem’s virtual power plants (VPPs) have been utilised to provide emergency demand response services in California during a major heatwave.

The networks, installed at a number of locations throughout the state, were used to meet increasing demand from air conditioning. The anticipated weather event created a spike in day ahead wholesale prices on 19 June, and a need to reduce demand or increase supply.

The services were provided to the California System Independent System Operator (CAISO) and three utilities.

“Stem proves again and again that we can step up immediately and deliver, right when the state or utility needs help,” said John Carrington, CEO of Stem. “When we are called, our network responds in minutes or less.”

This article requires Premium SubscriptionBasic (FREE) Subscription

Try Premium for just $1

  • Full premium access for the first month at only $1
  • Converts to an annual rate after 30 days unless cancelled
  • Cancel anytime during the trial period

Premium Benefits

  • Expert industry analysis and interviews
  • Digital access to PV Tech Power journal
  • Exclusive event discounts

Or get the full Premium subscription right away

Or continue reading this article for free

On June 20, Stem provided power to seven strained areas of the network. The aggregated assets dispatched 1.6MW of power within five minutes. During the rest of the week, there were a further 10 dispatches as the heat wave, and its impact on the grid continued.

In California, Stem uses the CAISO Proxy Demand Response (PDR) mechanism to aggregate distributed energy generators, and has been an active participant in the wholesale market over the last three years.

20 April 2027
Renaissance Dallas at Plano Legacy West Hotel, Dallas, Texas, Dallas
Policy, Procurement and Power Demand: Defining the Next Chapter for Energy Storage. Two days in Dallas where developers, IPPs, investors, utilities and the manufacturers building the technology come to close deals, not swap business cards. If you need to be in the room with the people deploying capital into US storage, this is that room.

Read Next

October 23, 2026
Tech giant Google and distributed energy resource (DER) platform Voltus have announced an expanded agreement to build a 1GW virtual power plant (VPP) in the US.
October 22, 2026
In recent North American sodium-ion news, Hithium is entering the Canadian market with two BESS solutions, while Peak Energy has closed a Series B financing round led by GM.
October 22, 2026
Science safety leader UL Solutions has announced a new certification pathway intended to help manufacturers of modular direct current (DC) battery energy storage systems (BESS).
October 21, 2026
Distributed energy storage company Viridi and developer and financier Good Carbon Co. have announced the deployment of a 3.75MWh energy storage project in Buffalo, New York.
October 20, 2026
Zinc hybrid cathode battery and storage system maker Eos Energy Enterprises has reported its highest quarterly revenue to date alongside a narrowing gross margin loss.