Xanterra Parks & Resorts Zion Lodge Water Recirculation System | Xanterra Parks & Resorts
“Resulted in significant annual water use reductions in an area of the country where water scarcity is a real concern. Innovative use of a heat exchanger and solar water heaters in the design and measured savings compared to the baseline years. It is also a local ‘native’ design that was accomplished to fit a particular application, however this new technology could also be adopted in other regions.”
--Environmental Leader Product & Project Awards judge
At Zion Lodge in Zion National Park, operator Xanterra Parks & Resorts uses a water-cooled system for walk-in refrigeration units in the Red Rock Grill kitchen. The units consumed water sourced from the Virgin River. This water was discharged along with wastewater created during the cooling process through a sanitary sewer system to a treatment facility outside the park in Springdale/Rockville, Utah. This river water, if conserved, would contribute to the vital flow of the Virgin River through Zion National Park. The river is responsible for carving majestic sandstone monoliths in scenic Zion Canyon. Its steep down cutting and periodic flashfloods contribute to the diverse array of plant and animal life that are key to the park ecology. In an engineering innovation, Xanterra and its contractors designed and installed a system that recirculates the refrigeration system cooling water, saving an estimated one million gallons of water per year.
The kitchen uses walk-in cooling units with water-cooled condensers, which are efficient in warm climates. The compression and vaporization of the refrigerant in the system cools the units, and heat is transferred to the condenser, which must be cooled along with the refrigerant. In this system, cold water was passed through the system, past the condenser and through the compressor, transferring heat from the system into the cool water. The used water was then discharged just past the compressors into the sewer system. Xanterra designed and installed a system that recirculates the water that is discharged after cooling the unit’s condenser. The water is redirected through a heat exchanger and two solar water heaters to extract heat. The water, now cool enough to be used again, then recirculates through the system, cooling the system over and over rather than constantly introducing new, cool, potable water.
One of the lodge’s goals was to reduce water consumption by 3% annually using a 2000 baseline. Since then, the property has reduced water consumption by 55%, 3.4% with this single project. Additionally contributing to Xanterra’s sustainability goals, the amount of greenhouse emissions saved an estimated 12.8 metric tons of carbon dioxide equivalent. Xanterra placed a meter at the discharge point to measure water flowing out of the cooling system over a period of about six months in 2012. During that time, more than 500,000 gallons of water flowed out to the sanitary sewer through the refrigeration system. Xanterra projects this relatively simple, but somewhat costly, design change results in a savings of more than one million gallons of water each year. Xanterra saw its water usage decrease in 2012 by nearly 800,000 gallons compared to 2011 due to this and other general water conservation measures.
Although the system design standard was to freely utilize new water in the condenser cooling process, an intelligent redesign saved valuable water without having to completely replace the equipment. This recirculation system was designed on-site by a local company for this specific unit. This allowed Zion Lodge to utilize the continued capacity of the existing equipment while increasing its resource conservation. This reinvention of existing technology is a key highlight for the lodge’s focus on innovation in the workplace and environmental ethic. The repair ethic is prevalent in Xanterra’s culture in order to reduce the societal costs of the greenhouse gas emissions from the manufacturing, transportation and subsequent energy used to recycle goods or dispose of them in a landfill, the company says.
Photo credit: Kim Fox Johnson