Providing real-time chiller plant operating efficiency expressed as either kW/ton or coefficient of performance (COP) to plant operations staff and management is an important operational tool for chiller plants today. In many climates and applications, chiller plants consume a major portion of the energy use of a complete facility. Also, chiller plants require ongoing maintenance to maintaiÅn top operating efficiencies. Integrating chiller plant efficiency monitoring along with the plant controls package helps the plant operating staff determine the most efficient configuration of equipment and settings for various load conditions, and it also helps the staff to schedule maintenance activities to ensure the highest levels of efficiency are maintained without the unnecessary expense of maintenance intervals that are more frequent than required.

This paper discusses approaches to instrumentation and monitoring system requirements for real-time chiller plant energy performance monitoring that provides useful efficiency information with cost-effective instrumentation. To ensure the monitoring equipment will be cost-effective, a minimum target chiller plant size of 750 tons is assumed. However, the use of monitored energy performance to maintain or improve plant efficiency can be applied to a chiller plant of any size.

Basic equipment configurations and marginal costs are discussed to help interested operators and designers develop such monitoring systems as a part of their chilled water plant design efforts.

Units: Dual