Add Laundry Ozone System to Washing Machines

Description

Laundry Ozone Systems have been used for years, primarily in the larger branded hotels. Advanced technology has resulted in lower production costs, increased efficiencies, and higher cleaning performances, such as brightness. As a result of these improvements, the addition of ozone equipment to existing laundry operations has become more widespread.

What is ozone? Ozone is a gas that’s produced in an ozone generator. An ozone generator takes in air and converts it into 90% oxygen. The oxygen is then electrically charged causing the oxygen atom to split. These atoms then reassemble and form the ozone gas (O3).

How does an ozone laundry system work? The ozone gas is injected directly into the wash wheel where it dissolves in the cold water, opens up the fibers and releases stains. Opening up the fibers makes the linens easier to dry and results in a decrease in drying time. After the wash cycle is completed, the ozone is then vented through a carbon tower and absorbed. It is important to insure safety in the laundry room by installing an ozone monitor. An ozone monitor should be set to alarm at 0.05 parts per million.

Adding ozone equipment to existing washing machines can completely eliminate a laundry’s need for hot water because ozone works best in cold water. It also reduces the wash cycle and dryer times by a combined 30%, thus allowing for more laundry productivity. In addition, the rinse cycle is reduced from two cycles to one allowing for a water/sewer savings. Because ozone leaves only oxygen behind, it is also environmentally friendly.

Laundry operations currently account for almost one-quarter of all water consumed in a typical hotel and 17% of the hot water annual heating costs. Hotels that install ozone systems in their laundry facilities will experience more productivity in their laundry operations. Shorter dry times, fewer chemicals, less water, electricity and natural gas, and less wastewater are some of the benefits of ozone systems. An added bonus to ozone laundry systems is the extended life of their linens. Typically, the life of linens is increased by up to 20% as a result of not using hot water and fewer chemicals being needed.

Business Case

A 300-room hotel believes they may have a potential opportunity to reduce energy and water consumption by adding ozone laundry systems to the existing washing machines. Before taking any action, they want to calculate the return on their investment. The computations listed below show the annual savings, the investment costs and the payback period for the installation of an ozone laundry system on each of their three existing washing machines. Laundry processed includes bedding (sheets, blankets, pillow cases) and towels (from rooms and swimming pool area), bath mats and robes. The laundry room consists of three 125 pound commercial washers. Twelve loads per day are laundered on average per machine, for a total of 4,500 pounds per day, six days per week.

Energy costs saved are taken from the EPA’s Energy Star calculator. The cost of an ozone laundry generator is $20,000. The labor cost to install one generator is $2,000. The total cost to convert the laundry operations to ozone is $66,000. Many local utility companies have ozone laundry systems in their rebate programs. Be sure to contact your local utility company before starting any project to determine if rebates are offered.

Calculations

For the calculation, the cost per gallon of water and sewage is $.02 (obtained from bills). The cost to heat hot water per gallon is $.04 per gallon (obtained from national average index). The cost to install one ozone generator system is $22,000 installed, including labor. Associated labor costs and gas/electric dryer cycle reduction times are not included in this calculation. 

# Daily Loads

 

Gallons Reduced/Load

 

Total Days

 

Total Water Sewage Saved

36

X

47

X

312

=

527,904

 

# Daily Loads

 

Hot Water Reduced/Load

 

Total Days

 

Total Hot Water Gallons Saved

36

X

114

X

312

=

1,280,448

Annual Savings
Annual Water/Sewer Savings: 527,904 x $.02 = $10,558
Annual Hot Water Savings: 1,280,448 x $.03 = $38,413
Total Annual Savings: $48,971  

 Investment  

 Payback  

Cost per Ozone Gen. Installed: $22,000
Number of Ozone Gen: 3

Total Investment: $66,000  

Investment: $66,000
Annual Savings: $48,971

Payback: 1.4 years  

 

Resources

Ozone Laundry System Reduces Hotel’s Operational Costs by 40 Percent 
Pacific Gas and Electric Company article on Ozone Laundry System rebates 
The Laundry Forum Facts vs. Fallacy on Ozone laundry Systems