Enter the cooling capacity (e.g., BTU/hr) and the input power (W) into the calculator to determine chiller efficiency as a coefficient of performance (COP). 

Chiller Efficiency Calculator

Enter any 2 values to calculate the missing variable

Chiller Efficiency Formula

The following formula is used to calculate chiller efficiency as the coefficient of performance (COP) when cooling is in BTU/hr and power is in watts (W). 

COP = C / (P * 3.41214)
  • Where COP is the chiller efficiency (coefficient of performance; dimensionless)
  • C is the cooling capacity (BTU/hr) 
  • P is the input power (W) 

To calculate COP, convert the cooling capacity to the same power units as the input power (or use the BTU/hr-to-watt conversion shown above), then divide cooling output by input power.

How to Calculate Chiller Efficiency?

The following two example problems outline how to calculate the chiller efficiency (COP).

Example Problem #1:

  1. First, determine the cooling capacity (BTU/hr). In this example, the cooling capacity is given as 140 BTU/hr.
  2. Next, determine the input power (W). For this problem, the input power is given as 200 W.
  3. Finally, calculate the COP using the equation above: 

COP = C / (P * 3.41214)

Inserting the values from above and solving the equation: 

COP = 140 / (200 * 3.41214) = 0.2051


Example Problem #2: 

Using the same process as above, first define the variables required by the formula. In this case, these values are:

cooling capacity (BTU/hr) = 300

input power (W) = 500

Entering these values yields:

COP = 300 / (500 * 3.41214) = 0.1759