Central Heat Pump Water Heater Load Flexibility
Developing Thermal Storage Controls for Central Water Heating Systems in Apartments
Redwood Energy, LLC
Recipient
Arcata, CA
Recipient Location
2nd
Senate District
2nd
Assembly District
$1,168,221
Amount Spent
Active
Project Status
Project Update
The Project is currently demonstrating the heat pump water heater LOCUS load control technology at one of the three sites with ongoing analysis on the performance of the system and function of the controller utilizing CalFlexHub dynamic price rates. The retrofits of the other two sites are in progress. In summary, the project team has:
• collected and analyzed data on the baseline performance of each CHPWH system
• undergone significant design work to create universal controller designs that work with each site’s unique system and for the applicability and scalability of the controller beyond this grant project,
• conducted simulated performance of the controller to understand the maximum amount of savings that can be achieved and to compare to the demonstration results,
• built lab mock-ups of the controller to test control sequences and the controller algorithms,
• and have created detailed building plans and 3D models of each system with the controller to communicate the design to installing contractors and beyond.
The Issue
Central water heating systems are usually both the largest peak load and largest annual energy load in an all-electric low-income apartment complex building in California. Because hot water consumption peaks in the morning and late evening, when rooftop solar arrays are less productive or unproductive, the consequence is higher energy bills, and greater emissions from non-renewable grid-sourced electricity and grid stress. On the other hand, none of the limited central heat pump control technologies on the market have real-time input parameters to reduce operational costs, greenhouse gas (GHG) emissions and grid stress while maintaining or improving tenant hot water services.
Project Innovation
This project demonstrates a new-to-market Load Optimization Control Using Storage (LOCUS) technology developed by ZYD Energy to enable flexible load management through hot water storage volume controls. The LOCUS technology uses optimization algorithms to automatically determine heat-pump water heater operation schedules based on hourly/sub-hourly electricity price or emission factors, as well as demand response signals and real-time operation conditions, while ensuring reliable hot water supply. The technology will be demonstrated in three multifamily residential sites located in three different climate zones.
Project Goals
Project Benefits
This project demonstrates an innovative control technology that enables central heat pump water heater technologies to achieve load flexibility with efficiency improvement to benefit ratepayers, and from load shifting a reduction of peak energy on the grid and GHG emissions.
Affordability
This agreement advances a control technology that can reduce and shift the building's peak electric load, while improving system efficiency. Assuming 5 percent of existing multifamily buildings adopt the LOCUS technology in 10 years, the estimated annual electricity bill reduction for customers is $5.6 million with an estimated annual peak demand reduction of 18 MW and annual electricity use reduction of 15.6 GWh.
Subrecipients
ZYD Energy, Inc.
Franklin Energy Services, LLC
Ecotope
Greg Pfotenhauer
Gabe Krause
Lonny Grafman
Match Partners
Redwood Energy, LLC
