Center for the Built Environment

A research team at the University of California, Berkeley was tasked with addressing technical questions arising from the implementation of residential programmable communicating thermostats (PCTs) in California to meet updates to Title 24 building code related to PCTs. The purpose of the project was to perform research, development, and demonstration tasks to: validate the California Energy Commission’s PCT vision, answer technical issues related to system integration and implementation, recommend a suitable technology for a statewide one-way communication system for PCTs, and develop a methodology to study the impact of PCTs on electrical demand. The team performed several tasks to achieve these goals.

The team validated the Energy Commission’s vision by concluding that it was possible for manufacturers to develop PCTs that: met the proposed Title 24 system interface requirements, could be sold at a retail price less than $100, and could be manufactured within the Energy Commission’s planned Title 24 timeline. This conclusion was the result of a concept for a minimum functionality PCT that was published as a bill of materials and validated with a working proof-of-concept demonstration.

The team researched PCT system interfaces and identified technical issues related to system integration and implementation that should be considered as part of the policy, technology, and system design related to PCT implementation.

The team reviewed technologies that could be used for statewide PCT communication and recommended the Radio Data System (RDS) technology as a suitable solution. The team demonstrated the feasibility of this technology and developed a site survey tool and methodology to study its real-world performance.

Finally, the team developed a load group simulation to characterize the result of PCT pricing and control signals and used the simulation to study certain demand response scenarios. The team found that rebound peak from demand response events can be significant and that strategies to manage this peak should be investigated further.