Project Info ACTIVE Project Title
Restaurant Field MonitoringProject Number ET22SWE0046 Organization SWE (Statewide Electric ETP) End-use Water Heating/DHW/HPWH Sector Commercial Project Year(s) 2022 - 2025
This field demonstration project in a full service restaurant involves pre-retrofit energy monitoring of existing domestic hot water systems, the installation of single-pass air-source heat pumps (HPs) and other efficiency measures, and post-monitoring of optimized systems. Hot water is primarily used for sanitation purposes in commercial kitchens. A 2013 study (CEC-500-2013-050) by Fisher-Nickel Inc. estimated gas-load for domestic hot water (DHW) in foodservice at 340 million therms per year across 85,500 facilities. This project intends to demonstrate the energy savings potential from shifting the primary hot water energy load from the existing gas-fired or electric resistance heaters to high-efficiency HPs. Load flexibility measures via controls will be utilized to operate only at off-peak periods between 9pm to 4pm to minimize restaurant operating cost and maximize grid benefits to California. Any potential operating cost increase from switching from primary gas heating to electric in a restaurant will be offset with sensible efficiency measures on the distribution system (e.g., addition of master mixing valves) and end-use equipment (e.g. heat recovery dishmachine). If possible, we will try to perform additional testing to isolate the energy savings impact of heat-recovery dish machine and the master mixing valve. This proposed HP retrofit ‘add-on' project will, by design, keep the existing water heater in place to serve a much lower heat load and serve as a backup, so as not to trigger health department review. Positioning this project as a retrofit add-on versus replacement or new build application has other benefits as well, since it removes a lot of risk associated with design, operation, maintenance, and operating cost. The HP and storage tank do not have to be sized to meet the winter design day load and handle the high variability in daily hot water use in this segment. This mitigates the space requirements and electrical panel capacity issues that are common in existing buildings.