California’s heat waves, electrification mandates, and rising load are testing the grid. Community choice aggregators (CCAs) are responding with virtual power plants (VPPs), programs that connect customer devices and behavior into one dispatchable resource.

In a recent Uplight webinar, Bridget Abenay of Sonoma Clean Power and Marco Santiago of San Jose Clean Energy shared what they have built, alongside Leah Goodman, Senior Account Manager at Uplight. Here are the highlights.

Why California and CCAs are leading on VPPs

Tight grid constraints and new demand from electrification and artificial intelligence (AI) workloads have made California a proving ground for VPP implementation. State policy has worked to make demand resources both dispatchable and revenue generating, further spurring deployment. California also has the devices, including a large base of smart thermostats and the highest adoption of electric vehicles (EVs), solar, and storage across the United States.

CCAs, Leah said, were “naturally born to create new ways to deliver energy to customers.” Sonoma Clean Power and San Jose Clean Energy are putting that into practice with programs built through Uplight’s Flex, which connects thermostats, EV chargers, batteries, water heaters, and behavioral demand response into a single dispatchable resource.

Sonoma Clean Power: start with behavior, then add devices

Sonoma Clean Power’s VPP, SCP Rewards, began with a behavioral demand response program during a ten-day heat wave in September 2022. Approximately 2,000 customers delivered roughly 500 kilowatts (kW). Although small next to a 52 gigawatt system, it showed that customer flexibility is real and measurable.

Today, the program has 15,000 enrolled resources and 6.1 megawatts (MW) of enrolled capacity, achieving a record 5.7 MW of demand reduction on Aug. 9. Behavioral demand response still delivers roughly six times the reduction of the automated fleet, while thermostats have grown to roughly 1.3 MW.

Bridget’s central lesson is that enrolled capacity is not available capacity. Customers can start enrollment and stall while connecting a device, so the team tracks who starts, completes, connects, and stays active. It also relies on the verified reductions Uplight calculates to see what capacity it can count on. “Operational work matters just as much as the technology,” she said.

Looking forward, California Energy Commission funding will help Sonoma Clean Power scale toward 7,500 enrolled devices, focused on income-qualified customers, disadvantaged communities, and customers who face technology barriers.

San Jose Clean Energy: three programs, one VPP

San Jose Clean Energy, a City of San Jose department serving 350,000 customers, built its Peak Rewards VPP as three programs so every segment has a way in.

• Peak Rewards for All (July 2024): Behavioral demand response with no devices required. Approximately 3,000 customers earn bill credits of $1 per kilowatt-hour reduced in summer, plus a $20 sign-up bonus.

• Peak Rewards for Smart Homes (May 2025): Thermostats, EV chargers, and batteries, with incentives set by device. Nearly 5,000 devices delivered 1.5 to 2.5 MW this past summer.

• Peak Rewards for Business (May 2023): Behavioral demand response for commercial accounts. Thirty-nine accounts deliver approximately 100 kW per event.

Events typically last two hours and the team calls them under three triggers: a California Independent System Operator (CAISO) energy emergency alert, a day-ahead price above $500 per megawatt-hour, and a forecast monthly peak. Uplight’s contract pays for performance, with milestone payments tied to a goal of 25 MW by 2028. The team targets 7.5 MW by the end of the fiscal year and 50 MW by 2029.

Lessons learned from both programs

• Measure delivered capacity, not only enrolled capacity. Enrolled megawatts show program size. Delivered megawatts show what the grid can count on.

• Add technology one step at a time. Sonoma Clean Power has seen behavioral demand response act as a strong place to begin and build an initial participation base. San Jose Clean Energy has experienced that every manufacturer has a separate agreement, so it is beneficial to confirm one part runs well before launching the next.

• Show customers their results quickly. Both CCAs heard that participants want visibility into their performance. In Marco’s words, “Getting them in the program is half the battle,” and keeping them takes equal effort.

• Use direct outreach to drive enrollment. San Jose Clean Energy found that ads build awareness, while direct email and community-based organizations drive enrollments.

Both programs are widening access, from renters in San Jose Clean Energy’s Peak Rewards for All to income-qualified households in Sonoma Clean Power’s VPP expansion.

Hear directly from the CCAs

Watch the full webinar to hear Bridget, Marco, and Leah walk through program design, results, and the questions they answered live.