IBPSA Webinar – Research Committee
In an attempt to electrify residential buildings, the state of California has shown strong support for heat pump water heaters (HPWHs). As a result, CBECC-Res users have many HPWH manufacturers and products that they can analyze when demonstrating Title 24 residential code compliance. Joint Appendix JA13 to Title 24 provides the requirements for a HPWH to provide daily load shifting for the purpose of user bill reductions, maximized solar self-utilization, and grid harmonization. This presentation will showcase new CBECC-Res capabilities that enable the analysis of such daily load shifting strategies:
• Forcing off electric resistance and/or compressor heating components
• Forcing the HPWH to run with either resistance or compressor heating to “top off” tank or increase to higher setpoint
• Altering the tank setpoint
This presentation will also discuss an analysis using these new CBECC-Res capabilities that was conducted for six HPWH products that meet JA13 requirements. The main goal of this analysis was to develop demand-response schedules that minimized annual time-dependent value (TDV) of water heating energy. This analysis showed that when the developed demand-response schedules were compared to schedules without daily load shifting, reduction of annual water heating TDV energy across all California climate zones ranged from 1-8% for 2019 TDV values and 4-24% for 2022 TDV values.
Aaron Boranian is a Senior Engineer and the lead trainer at Big Ladder Software, where he is responsible for developing and delivering training material for the EnergyPlus building energy simulation engine, two of its interfaces (DesignBuilder and OpenStudio), and the California Simulation Engine (CSE) used by CBECC-Res for code compliance of residential buildings in California. To date, he has led over 70 workshops and trained over 650 people on these topics. Aaron is also involved in support and consulting projects where he uses these simulation tools for clients in various capacities.
Ben Larson has been researching heat pump waters for over a decade to understand their potential for both energy savings and load shifting. He has overseen numerous lab and field studies and co-developed the water heater simulation used in CBECC-Res. He is a principal at Larson Energy Research.
AIA Learning Objectives
1. Understand how domestic hot water draw events are simulated in CBECC-Res
2. Understand capabilities of CBECC-Res for modeling demand response strategies for controlling heating elements of heat pump water heaters (HPWHs)
3. Understand capabilities of CBECC-Res for altering the tank setpoint of heat pump water heaters (HPWHs)
4. Understand parameters (climate zone, number of bedrooms, etc.) that affect the development of a control schedule for HPWH demand response strategies