Retrofit Zoning Enhancement and Balancing Controls Field Assessment

The purpose of this HVAC Retrofit Zoning Control (HRZC) Field Monitoring Assessment is to confirm the annual energy usage and savings due to the HRZC technology assessed in Rancho Cucamonga, California. The results of the study will help to enhance Southern California Edison’s (SCE) Energy Efficiency (EE) and Demand Response (DR) program offerings. The American Society of Heating, Refrigeration and Air Conditioning Engineers 14-2014 (ASHRAE 14-2014) guideline was used to estimate potential savings due to the HVAC retrofit zoning control. The ASHRAE 14-2014 guideline sets forth instrumentation and data management guidelines and describes methods for accounting for uncertainty associated with models and measurements. Compliance with ASHRAE 14-2014 requires that the overall uncertainty of the savings estimates be below prescribed thresholds. Based on the electrical and zonal temperature data collected, this field assessment determined that the HRZC technology delivers better thermal performance compared to incumbent setback programmable thermostat technologies and effectively satisfies human conform conditions in both economy and comfort modes. When the HRZC settings switch from comfort to economy mode, maximum energy savings are achieved as the setback temperature (80˚F) at night will achieve deeper energy savings compared to economy mode (76˚F) and is less aggressive in attaining and maintaining desired setpoints (e.g., 72˚F in office spaces and 66˚F in employee locker rooms). In comfort mode, the desired temperature range swings much less as the HRZC aims at aggressively attaining and maintaining desired setpoints, which result in more energy use. The annual estimated energy savings achieved were 1,691 kWh (20% savings) for the office space and 2,841 kWh (52% savings) for the locker rooms when comparing the HRZC post retrofit scenario with the pre-commissioning energy baseline use.