AT-19-C035 -- Next-Generation Residential Space Conditioning System for California

The Next Generation Residential Space Conditioning System for California (Next Gen RSCS) is an integration of multiple advanced HVAC technologies including: a variable capacity compressor, variable speed blower fan, automated demand response, fault detection and diagnostics, intelligent dual fuel heating (gas/electric), integrated ventilation, and zonal control. In addition to these features, an alternative refrigerant, (R-32), was evaluated as a possible future enhancement. Along with these technology evaluations, an assessment was performed on duct losses for single versus multi-zone duct configurations with variable capacity equipment. The experimental results, from 3 leading U.S. laboratories, provide information to the industry on optimizing the system for efficiency, utility integration, and homeowner comfort. Key findings from the laboratory evaluation of the Next Gen RSCS included: - Cooling energy savings range between 22-32% for California (CA) compared to a 14 SEER single speed baseline system. - The system satisfies over 90% of annual heating load for most of CA without electrical or natural gas back-up. - Demand response capability with variable capacity equipment enables utilities to reduce peak demand while reducing customer discomfort. - Revising ducting standards and providing more efficient control strategies would improve the integration of heat pumps connected to attic ductwork for hot and dry California climates. - Zonal control, integrated ventilation and intelligent heating deployed with the Next Gen RSCS offer energy cost savings and system versatility. - Heating and cooling mode experimental results of the Next Gen RSCS with R-32 as a drop-in refrigerant demonstrated comparable or improved performance to R-410A. The Next Gen RSCS is under field evaluation in 3 homes in the CA Investor Owned Utility (IOU) service territories (PG&E, SCE, and SDG&E). The presentation will include an assessment of the technologies’ performance studied in the laboratory and associated modeling, as well as the status of the field evaluation and the methodology employed.