This paper describes the basis for an energy efficient refrigerant-based thermal energy storage system design for commercial DX systems. A description of a system is given, and design aspects contributing to energy efficiency are identified. Similarly, operating characteristics and strategies contributing to energy efficiency are discussed. Challenges in measuring and predicting energy efficiency are identified, along with a proposed method for collecting certified performance data, and sample test results. Field data is then analyzed to determine if it is consistent with energy savings predictions. The benefits of using such energy efficient thermal energy storage systems are then considered for several climate zones. Results show that refrigerant-based thermal energy storage for commercial DX systems is energy neutral or better given specific design considerations and operating strategy.

Units: Dual