Page 99 - WaterSense at Work

October 2012
Commercial Ice Machines
to rinse more frequently than needed, not taking into account the facility’s incoming
water quality and resulting in wasted water.
In addition to equipment rinsing, some facilities require a higher
quality of ice than other facilities, depending upon the end use
of the ice. A restaurant serving ice in beverages, for example,
might want very clear, high-quality ice, while a cafeteria using ice
to cool prepared food in a display case might not be concerned
with the clarity of the ice used. Some ice machines are designed
to produce clearer and smoother ice using a repeated freez-
ing and partial thawing process. This method produces ice with
fewer air bubbles and is more crystalline, but the process uses
more water.
The types of ice that ice machines can make include:
Cubed ice—clear, regularly shaped ice weighing up to 1.5
ounces per piece and containing minimal amounts of liquid
Flake ice—chips or flakes of ice containing up to 20 percent
liquid water by weight.
Crushed ice—small, irregular pieces made by crushing bigger pieces of ice.
Nugget ice—small portions of ice created by extruding and freezing the slushy
flake ice into a nugget.
Cubed ice machines are the most prominent in the market, accounting for approxi-
mately 80 percent of ice machine sales in the United States.
Most cubed ice ma-
chines use more water than flake ice machines because they run more water over the
freezing ice to remove sediment and minerals left as the water freezes. In general, the
higher the quality of ice, the more water is needed for the ice-making process.
Water used for the ice-making process ranges from 15 gallons to more than 50 gal-
lons per 100 pounds of ice,
depending upon the amount of water used to rinse the
ice-making surfaces and the amount of water needed to produce higher quality ice.
In total, including the ice-making and cooling processes, water-cooled ice machines
with single-pass cooling consume between 100 and 300 gallons of water per 100
pounds of ice produced,
while air-cooled ice machines can consume less than 50
gallons of water per 100 pounds of ice produced. While air-cooled machines are usu-
ally more water-efficient, water-cooled machines are usually more energy-efficient.
Some air-cooled units, however, are able to match or exceed the energy efficiency of
water-cooled units while also providing substantial water efficiency.
Pacific Gas and Electric Company.
Information Brief: Commercial Ice Machines
Koeller, John and Hoffman, H. W. (Bill). Koeller and Company. June 2008.
A Report on Potential Best Management Practices—Commercial Ice Machines
Prepared for the California Urban Water Conservation Council. Page 6.
Bohlig, Charles M. East Bay Municipal Utility District. February 7, 2006. “Water Efficiency in Commercial Food Service.” Slides 13-20.
op. cit.
Crushed ice machine