# Page 102 - WaterSense at Work

4-8
October 2012
4.2
Commercial Ice Machines
Current Water Use
To estimate the current water use from a water-cooled ice machine, identify the fol-
lowing information and use Equation 4-1:
••
The ice machine’s harvest rate, or how many pounds of ice it produces per day.
••
The ice machine’s maximum water use rate. EPAct of 2005 provides different
water use maximums for water-cooled, self-contained units with harvest rates
less than 200 pounds per day and those with harvest rates greater than or equal
to than 200 pounds per day. It also provides different water use maximums for
water-cooled, ice-making head units with harvest rates less than 500 pounds
per day; those with harvest rates greater than or equal to 500 pounds per day
and less than 1,436 pounds per day; and those with harvest rates greater than or
equal to than 1,436 pounds per day.
19
••
Days of facility operation per year.
Equation 4-1. Water Use of Ice Machine (gallons per year)
= Harvest Rate xWater Use Rate x Days of Facility Operation
Where:
••
Harvest Rate (pounds of ice per day)
••
Water Use Rate (gallons per 100 pounds of ice)
••
Days of Facility Operation (days per year)
Water Use After Replacement
To estimate the water use of a replacement air-cooled model, use Equation 4-1,
substituting the harvest rate (if it will change) and the new water use per hundred
pounds of ice. ENERGY STAR provides different water use maximums for qualified air-
cooled models depending on the machine type and the harvest rate.
20
Water Savings
To calculate the water savings that can be achieved from replacing an existing water-
cooled ice machine, identify the following information and use Equation 4-2:
••
Current water use as calculated using Equation 4-1.
••
Water use after replacement as calculated using Equation 4-1.
19
Energy Policy Act of 2005. Public Law 109–58. August 8, 2005.
20
EPA and DOE’s ENERGY STAR. Commercial Ice Machines Key Product Criteria,
op. cit.