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

Enjoy 12 months of exclusive analysis

Not ready to commit yet?
  • Regular insight and analysis of the industry’s biggest developments
  • In-depth interviews with the industry’s leading figures
  • Annual digital subscription to the PV Tech Power journal
  • Discounts on Solar Media’s portfolio of events, in-person and virtual

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.

Read Next

Premium
October 7, 2025
Energy-Storage.news Premium hears from a representative from Honeywell and Alejandro Schnakofsky, CTO of Prevalon, on fire safety in the battery energy storage system (BESS) industry.
October 7, 2025
Utility CPS Energy and IPP Eolian have begun operating Padua 1, a 50MW/100MWh battery energy storage system (BESS) located in Bexar County, Texas, US.
October 6, 2025
Nightpeak Energy has announced commercial operations of its 150MW/300MWh Bocanova Power battery energy storage system (BESS) in Brazoria County, Texas, US.
October 3, 2025
EDF Renewables has brought its 300MWh Milagro project online in New Mexico, while Enlight Renewable Energy has secured US$340 million in tax equity financing for its 940MWh Roadrunner project in Arizona.
October 2, 2025
Major US utility company Duke Energy has filed its biennial long-range energy modernisation plan for North and South Carolina, US. The plan includes a 5,600MW battery storage target.

Most Popular

Email Newsletter