Evaluating the uncertainty in cool storage inventory using an energy balance method

Conference · Thu Jul 01 04:00:00 EDT 1999

OSTI ID:20085693

D'Albora, E G; Gillespie, K L

Instrumentation was installed at a large convention hotel in San Francisco to monitor the performance of the chilled-water plant with cool storage. The instrumentation was intended to provide the basis for evaluating advanced control technology, including real-time optimization of the plant, electricity price-based control, and enhanced scheduling. These capabilities were to be incorporated into a new building management system, which would also provide performance monitoring and data management. Fundamental to performance optimization of a chilled-water plant with cool storage is the need to know the state of charge or storage inventory (sensible and latent) of the cool storage system. Both instrument error and storage standby loss offer potential impediments to balancing thermal flows over any give storage charge/discharge cycle or series of cycles. In this project, the authors attempted to measure storage inventory using accurate instrumentation familiar in the HVAC environment while employing proper installation and advanced field calibration techniques. They utilized a series of tests along with an uncertainty analysis in an attempt to evaluate what error tolerance is required to maintain a predictable measure of present and future inventory levels. In this paper, the authors examine what influences the uncertainty in the storage inventory calculation, evaluating both theoretical possibilities and the as-measured conditions. They also compare measured results with that of factory-supplied ice capacity transmitters.

• Research Organization: Pacific Gas and Electric Co., San Ramon, CA (US)
• OSTI ID: 20085693
• Country of Publication: United States
• Language: English

Related Subjects

25 ENERGY STORAGE
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION
CALIFORNIA
COLD STORAGE
CONTROL SYSTEMS
DATA COVARIANCES
ENERGY BALANCE
HOTELS
ON-LINE MEASUREMENT SYSTEMS
SENSITIVITY ANALYSIS
SPACE HVAC SYSTEMS
THERMAL ENERGY STORAGE EQUIPMENT