Smart-Panel Integrated Variable Speed Heat Pumps

This project will demonstrate variable-speed heat pumps (VSHPs) integrated with smart electric panels that will actively manage household electrical loads, including compressor and air handler speed for the VSHP. By modulating the speed in real-time according to panel capacity and grid conditions, VSHPs can maintain partial operation during peak periods, preserving comfort while easing panel and grid strain. The approach overcomes a major barrier to widespread electrification in California: the prevalence of homes with limited electrical service, often 100 amps or less. These "panel-limited" homes cannot easily support central heat pumps along with other electric loads without expensive panel or service upgrades. Traditional single speed heat pumps (SSHPs) generally rely on electric resistance backup during defrost cycles, which requires substantial panel capacity (can reach 80+ amps) and results in high peak demand during cold weather. Since SSHPs have no ability to modulate load, their integration with smart electric panels brings little benefit (other than on/off control). SSHPs are typically sized to meet peak heating or cooling loads, thus are oversized for much of the year. During part-load conditions, they cycle on and off frequently, consuming more panel capacity than necessary and causing efficiency losses. Their inability to modulate output complicates maintaining occupant comfort, especially when panel constraints or demand response events require load reduction. In such cases, SSHPs can only be turned off entirely, leading to full loss of heating or cooling rather than gradual reduction.The project will gather real-world load data from a sample of California homes that have already installed smart panels to analyze the available electrical capacity for heat pump operation. Smart panels have been increasingly adopting open communication protocols   (such as “Matter”) to integrate with home area networks and HVAC systems. In a controlled research home, the team will test the performance of an smart electric panel controlling a VSHP system (with open communications) with dynamic load management and compare that to a smart panel controlled SSHP (on/off control). This project will evaluate smart panel integrated VSHP performance to inform utility rebate programs. It will assess whether the system enables electrification without service upgrades, reduces peak demand while maintaining comfort, and outperforms traditional single speed systems in efficiency and demand flexibility. The findings will help determine its potential for inclusion in incentive programs by demonstrating cost effectiveness, grid benefits, and suitability for California homes with limited electrical capacity.