There are many opportunities for commercial kitchens to increase energy efficiency and save money. One area that is often overlooked is pre-rinsing dishes before they are placed in the dishwasher.
Conventional pre-rinse spray valves (PRSVs) consume up to one-third of the water used in a commercial kitchen, according to the U.S. Environmental Protection Agency (EPA). The EPA estimates that the nearly one million food service establishments throughout the country use approximately 51 billion gallons of water every year to rinse dishes.
Many commercial kitchens still use valves with flow rates exceeding the current federal standard maximum of 1.6 gallons per minute (gpm). The Food Service Technology Center recommends replacing these high-flow valves with PRSVs that meet the federal standard, as long as they have a cleaning performance of 26 seconds per plate or less (based on the ASTM Standard Test Method for Performance of Pre-Rinse Spray Valves). A variety of products are available that match these requirements.
In one case, switching to a 1.6-gpm valve resulted in an annual savings of about $400 per sprayer for water, sewer and natural gas.
Save even more
In 2013, the EPA introduced the WaterSense label for PRSVs, which sets the maximum flow rate at 1.28 gpm, or 20 percent less than the federal standard. Other requirements for the WaterSense label include:
Replacing just one conventional fixture with a WaterSense labeled model can save a typical restaurant more than 7,000 gallons of water per year, the amount of water needed to wash nearly 5,000 racks of dishes. This translates into savings of as much as $115 to $165 per year in water and energy costs. Annual natural gas use can be reduced by more than 4,250 cubic feet per year, which is enough energy to run a convection oven 8 hours a day for two weeks. The payback for replacing one fixture is just four to eight months.
If every U.S. commercial food service establishment installed and used a WaterSense labeled valve, the country could save more than 10 billion gallons of water and more than $225 million in water and energy costs each year, and prevent the equivalent of emitting carbon dioxide from 187,500 vehicles.
Boston Pizza replaced its conventional valves with low-flow models at one of nine locations for annual energy and water cost savings of $1,060. Average annual savings per valve was about 1,000 kilowatt hours (kWh) of electricity and 7,000 gallons of water.
A pilot project conducted by the city of Calgary (Canada) identified an average savings of about 95 gallons a day per valve. The average water and energy savings over the five-year life expectancy of the valves in participating facilities was approximately $1,300 for gas water heating and $1,600 for electric. The installed cost was approximately $135.
See the Food Service Technology Center’s Pre-Rinse Spray Valve and Water Cost Calculator to estimate how much an upgrade can save your facility.
Your electric and gas utilities offer incentives for purchasing energy efficient kitchen equipment. For more information, see our Save@Work section.
This article has been prepared solely for the purpose of providing helpful information to users of this service. The information has been compiled by Questline, a contractor to the NHSaves utilities; however, no representation is made by either Questline or NHSaves as to the completeness or accuracy of the information contained therein. In particular, some information may be incomplete, may contain errors or may be out of date. In addition, neither Questline nor NHSaves endorses any product or service mentioned therein.