Minneapolis Hilton Proves Energy Savings with Ozone Laundry

A study of the ozonated hotel laundry equipment in the Hilton’s on-premise laundry proved that ozone reduced the overall costs of the laundry operation by 24% while still delivering the fluffy towels and crisp, clean linens guests enjoy. The investment for these savings was repaid by the savings in just 13.5 months.

A summary report (PDF opens in new window) of this research can be found at the Energy Solutions Center of Washington DC, an organization that supports the development of innovative energy conservation techniques in a wide range of industries and applications.

The Minneapolis Hilton On-Premise Laundry Test

In 2008, the Minneapolis Hilton and the National Energy Services Company* (NESC) teamed up to demonstrate the effectiveness of ozone laundry for this 821 room hotel.  The hotel washes 3.5 million pounds of laundry every year in its on-premise laundry.  The main objective of the project was to show how using ozone injection for laundry sanitation could reduce energy costs. 

A 4-month test period was set up to measure important input variables and monitor key outcomes closely. NESC installed four DEL Ozone laundry ozone generators on the existing hotel laundry equipment.  The researchers measured hot water use, energy consumption, and fabric softener use on the input side, and monitored the quality of linens output including the amount of items needing replacement.

Ozone On-Premise Laundry Outcomes

This well-designed ozone laundry system produced enough energy savings to allow the Minneapolis Hilton to qualify for an energy conservation rebate from CenterPoint Energy, Inc., the local utility. The ozone laundry system reduced hot water use by 55%, which was the core source of the savings, allowing the Hilton to replace 4 old, inefficient water heaters with just two new high-efficiency condensing boilers.

Some important outcomes included:

• Reduced overall laundry costs by 24%.
• Reduced hot water use from 198 gallons to 89 gallons per loador total daily use from 8,500 4,000 gallons, a 55% savings.
• Saved 33,000 therms energy use per year.
• Reduced the need for re-wash by half.
• Eliminated the need for fabric softener.
• Extended linen life by eliminating the damaging affects residual alkilide, while keeping soft, fluffy laundry.
• Reduced the hotel carbon footprint by over 209,000 pounds per year.

The ROI of Ozone Laundry

The bottom line is healthy in an ozone on-premise laundry, as the Hilton study shows.  The ozone laundry system was projected to pay back the initial investment in just 13.5 months (a return of 89%), with on-going savings accumulating from that point forward.

For this performance DEL Ozone was rewarded by being made a preferred vendor for Hilton Supply Management.

* The ozone laundry unit of NESC was integrated into DEL Ozone in January 2010. All of the ozone machines used in this test were DEL Ozone production units and DEL system components.