How Illinois is Unlocking Access to Significant VPP Capacity
Around the country, customers’ utility bills are increasing, driven largely by soaring energy demand. This is the case in Illinois. Commonwealth Edison Company (ComEd) serves the northern portion of the state and reported receiving applications representing an additional demand of 28 GW between January and August 2025. That is more than 4 GW above the utility’s record peak summer load, which occurred in July 2011. Because of the increased energy demand and inadequate supply, PJM’s capacity auction prices have spiked, reaching $333.44/MW-day for the 2027-2028 versus $68.96/MW-day for 2022–2023.
ComEd is the fourth largest electric utility in the United States, and its price increases affect approximately 4 million customers. With the increasing capacity costs and anticipated load growth, every kilowatt counts. Fortunately for ComEd’s customers, on Wednesday, June 24 the Illinois Commerce Commission (ICC) approved a settlement agreement establishing a new smart thermostat load reduction program designed to allow customers to use devices they already own to support the electric grid in times of system constraint. This will reduce costs for all consumers. In exchange for supporting the grid, customers receive compensation commensurate with their contributions. The first day of the program is expected to be May 1, 2027. The initial version of the “Bring Your Own Device (BYOD) Load Reduction” program focuses on two types of distributed energy resources: smart thermostats and thermal storage devices, such as ice-based thermal storage systems or chilled water storage systems in commercial buildings. United anticipates this program will be folded into a future virtual power plant (VPP) program.
Advanced Energy United led the charge for the smart thermostat component, pushing for the inclusion of this technology since the effort began in 2024. ComEd proposed the thermal storage component later in the process. Under the model approved by the ICC, ComEd can call upon hundreds of thousands of smart thermostats already in use to adjust cooling load, freeing up hundreds of megawatts on short notice to accommodate fluctuations in load on the company’s distribution system. In exchange for accepting minor temperature adjustments, thermostat owners receive compensation based on the average of their contributions to the grid.
A new innovation of the planned VPP program design is a pathway for original equipment manufacturers (OEM) to enroll people who previously purchased smart thermostat or thermal storage products. Some smart thermostat OEMs ask customers during the installation process if they are willing to participate in programs that benefit the grid if the opportunity arises. These people will be able to participate without having to separately enroll in ComEd’s program. This means smart thermostat OEMs with lists of consenting purchasers within ComEd’s service area can enroll those purchasers and adjust their thermostats as soon as the OEM enrolls in the program.
United member companies helped lead during this process. EnergyHub, Renew Home, Generac, and ecobee plan to make use of this program.
“Illinois utility customers are facing rising electricity bills driven by surging demand, and programs like ComEd’s BYOD Load Reduction are exactly the kind of solution that benefit all customers’ bills,” said Monisha Shah, Director, Regulatory Affairs at EnergyHub. “VPP programs have delivered real savings for customers in comparable markets. Illinois now has its chance to do the same.”
“ComEd and the joint parties got the hard part right: they made participation effortless. Through the OEM enrollment pathway, customers who already opted in with their device manufacturer can begin supporting the grid and earning for it without a separate sign-up. That’s a real step toward lowering costs for every ComEd ratepayer, not just the ones who participate,” said Will Baker, Head of Market Development at Renew Home.
“ecobee is proud to support a program that demonstrates the real grid value of smart thermostats. Illinois has taken an important step toward showing how connected devices can be mobilized as a clean, flexible and cost-effective grid resource,” said Jena Ginsburg, Senior Manager of Policy and Regulatory Affairs at ecobee/Generac.
When United first started designing this program with ComEd in 2024, we focused on attracting participants and delivering meaningful results. The VPP-related provisions in the Clean and Reliable Grid Affordability Act (CRGA) almost led to the delay of a smart thermostat program until 2029. United and an aligned intervenor, however, succeeded in preserving the case at the ICC and ultimately producing a settlement agreement among ComEd, United, and several environmental organizations.
ComEd still plans to evaluate the cost effectiveness of the program before implementation, and must share the results of its cost-effectiveness analysis later this year. With multiple other electric utilities already operating similar programs, United expects ComEd will find the program beneficial to its customers. This outcome is more likely if ComEd learns from the similar efforts of its affiliates Atlantic City Electric Company, Baltimore Gas & Electric Company, and Delmarva Power & Light Company.
While the program approved by the ICC will not address all of the growing demand ComEd foresees, it represents a meaningful step toward making use of existing resources to deliver capacity at low cost.