Concerns about maintaining optimum operating conditions for central plants in order to minimize energy usage and cost have highlighted the need for accurate measurements of electrical power, fluid flow, and temperature chillers and boilers. In particular, chiller efficiency, typically expressed in units of kW/ton, can vary with a number of factors, including condenser and evaporator temperatures and compressor loading. Maintaining the optimum chiller efficiency requires the capability of measuring flow, power, and temperature on a continuous basis and with sufficient accuracy to enable the determination of chiller efficiency. This paper addresses the requirements for a measurement system for assessing chiller efficiency as part of a general energy management and control system for central plant operation.

Units: Dual