There are two main retrofit options to reduce
water use associated with existing laundry equipment: water reuse/recycling and
Simple or complex recycling systems can be
added to coin- or card-operated washers, multi-load washers, and washer
extractors to recycle a portion or all of the water for reuse in the next wash.
Simple recycling systems recover discharge from the final rinse in a
multi-cycle operation for use in the first rinse of the next cycle. The water
from these systems rarely needs treatment prior to reuse, so potential water
savings is 10 to 35 percent. Complex recycling systems treat the reclaimed
water from wash and rinse cycles for use in all cycles of the next load and can
save more than 85 percent of water used. Complex recycle systems usually
require water treatment before reuse. Be sure to evaluate space constraints
when considering water reuse/recycling options. Space may not be available to
accommodate additional recycling equipment or storage tanks. Because recycling
may also require adjustments in chemicals and detergents, contact the chemical
supply vendor in any retrofit planning.
Ozone systems can be installed on all types
of existing commercial laundry machines as retrofits, although they are not as
common as a retrofit for tunnel washers. Ozone systems generate ozone, which is
injected into the wash as a powerful oxidant that reacts with dirt and organic
materials. It also provides disinfection and whitening properties. Ozone can
allow for reduced water temperatures, typically to 80oF, which saves energy. It
also can reduce the amount of detergents and other chemicals needed, lessening
the amount of rinsing required. Ozone systems work well on lightly soiled
laundry, but they are not recommended for heavily soiled laundry. For heavily
soiled laundry, conventional washing, detergents, and hot water work best.
Water savings can be achieved through
retrofitting existing laundry equipment to recycle wash water or reduce the
amount of water required for rinsing, or by replacing existing laundry
equipment with more efficient equipment. To estimate facility specific water
savings and payback, use the following information.
Coin- or Card-Operated Washer or Multi-Load Washer Retrofit
Use the following information to estimate
water savings and payback potential that may be achieved with recycling or
ozone retrofits. Water savings can vary based upon the water use and use
patterns of the existing laundry equipment and the type of retrofit selected.
Current Water Use
To estimate the current water use from a
commercial coin- or card-operated washer or multi-load washer, identify the
following information and use Equation 1-1:
Washer’s water factor in gallons per cycle per cubic foot of capacity.
Coin- or card-operated washers installed since the early 1990s will have a
water factor of 9.5 gallons per cycle per cubic foot of capacity or less.
Capacity of the washer.
Average number of cycles per load. The number of cycles refers to the
number of times the washer is filled with water. There may be one or two wash
cycles and one or two rinse cycles in typical coin- or card-operated washers or
Average number of loads per year.
Water Use of Commercial Coin- or Card-Operated Washer or Multi-Load Washer
= Water Factor x
Washer Capacity x Number of Cycles x Number of Loads
• Water Factor (gallons per cycle per cubic foot capacity)
• Washer Capacity (cubic feet of capacity)
• Number of Cycles (cycles per load)
• Number of Loads (loads per year)
Studies have documented water savings for
retrofits with a simple recycling system, retrofits with a complex recycling
system, and ozone system retrofits.
1-2. Potential Water Savings from Commercial Laundry Retrofit Options
Simple Recycling System
10% to 35%
Complex Recycling System
85% to 90%
Retrofit With Ozone
10% to 25%
31 East Bay Municipal Utility District (EBMUD). 2008. Water
Smart Guidebook: A Water-Use Efficiency Plan Review Guide for New Businesses.