System and method for determining efficiency of chillers

A method for generating an efficiency curve of a chiller, comprising:

• operating a chiller over a range of operating capacities of the chiller;
• measuring, at a first operating capacity within the range of operating capacities of the chiller, a first temperature of water entering the chiller using a first probe disposed in a water delivery conduit;
• measuring, at the first operating capacity, a second temperature of water exiting the chiller using a second probe disposed in a water discharge conduit;
• measuring, at the first operating capacity, a first power consumption of the chiller using a variable speed drive control;
• calculating a first efficiency value of the chiller at the first operating capacity based on the first temperature, the second temperature, and the first power consumption;
• measuring, at a second operating capacity within the range of operating capacities of the chiller, a third temperature of water entering the chiller using the first probe;
• measuring, at the second operating capacity, a fourth temperature of water exiting the chiller using the second probe;
• measuring, at the second operating capacity, a second power consumption of the chiller using the variable speed drive control;
• calculating a second efficiency value of the chiller at the second operating capacity based on the third temperature, the fourth temperature, and the second power consumption;
• and
• generating an efficiency curve for the chiller using the first efficiency value and the second efficiency value.

A method of continuously determining an efficiency of a chiller during operation of the chiller, comprising:

• measuring an input variable of the chiller, an output variable of the chiller, and an operating variable of the chiller at a first operating capacity of the chiller;
• calculating a first efficiency value of the chiller at the first operating capacity;
• measuring the input variable of the chiller, the output variable of the chiller, and the operating variable of the chiller at a plurality of second operating capacities of the chiller;
• calculating a plurality of second efficiency values of the chiller at each operating capacity of the plurality of second operating capacities of the chiller;
• and
• generating an efficiency curve of the chiller based on the first efficiency value and the plurality of second efficiency values.