U.S. Department of Energy

Background:  The U.S. Department of Energy (DOE) Building Technologies Office seeks to develop and accelerate the integration of energy efficient technologies and solutions into new and existing buildings. An area of interest is multi-load washers used in the healthcare and hospitality industry because they are among the most energy intensive pieces of equipment used in these facilities. Multiple technologies are available on the market for significantly reducing energy and water consumption of multi-load washers. However, adoption of these advanced technologies has thus far been limited because of uncertainty about return on investment and concerns about reliability, performance, and user satisfaction, including hotel guest/healthcare patient satisfaction. Quantifying the energy and water savings potential of current market-ready systems will help promote the adoption of these technologies in the commercial sector.

The objective of this demonstration project was to evaluate market-ready retrofit technologies for reducing the energy and water use of multi-load washers in healthcare and hospitality facilities. Specifically, this project evaluated laundry wastewater recycling technology in the hospitality sector and ozone laundry technology in both the healthcare and hospitality sectors. This report documents the demonstration of two ozone laundry system installations. The demonstration of a wastewater recycling system is documented in a separate report.

Problem: Most institutional laundry systems found in on-premises hospitality and healthcare facilities are batch systems, using multi-load washers (MLWs) and washer extractors with thousands of pounds of throughput daily. MLWs and washer extractors are among the most energy intensive equipment in these facilities. Improvements in efficiency in batch laundry MLWs are available from system improvements or retrofits. These retrofits are commonly either 1) a low-temperature ozonation system supplementing traditional hot water-based detergents; or 2) a wastewater recycling system that reduces total water consumption.

Solution:  The ozone laundry system used for this demonstration project delivered significant hot water energy savings of 65% and total water savings of 15%. The demonstration site in Charleston, SC is characterized as having relatively moderate natural gas prices and water/sewer rates. The significant cost savings provided by the ozone system results in a simple payback period of 2.8 years. The results of this study indicate that ozone laundry technology is a financially attractive investment for hotels with similar laundry and utility characteristics as the Charleston Place Hotel.