The City of Santa Rosa conducted a pilot rebate program for hotes and commercial laundry facilities to use ozone. It was part of a larger state wide program determine the amount of energy consumed by various water using applications. Specifically the program tried to quantify the water and energy savings assocaited with ozone laundries versus conventional approaches. The study focused on hotel laundries. Ozone allows for laundries to achieve equal cleaning, but with cold versus hot water.
At the sites studied, hot water use at the facilities decline 98%. This reduced energy consumption, specifically natural gas, used to heat the water. The average savings was 10,247 therms/year directly by saving hot water. Natural Gas is usually measured by volume, cubic feet. A cubic foot of gas is the amount of gas needed to fill a volume of one cubic foot under set conditions of pressure and temperature. To measure larger amounts of natural gas, a “therm” is used to denote 100 cubic feet.
The use of ozone also allowed the average hotel to save 911,000 gallons of water per year and this in turn was assocaited with a further energy savings of 7,190 kwh/year. All of these savings resulted in a total reduction in utility costs of $13,000/year on average at the time of the study.
The city offers rebates to encourage the use of energy and water saving technology. They have found that saving water is cheaper than trying to develop new water sources for the city. the payback periods on teh rebates cna range from a few months to two years. In general, a very good investment.