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Technologies - Kitchen Equipment


Kitchens, whether residential or commercial, typically include several water-using appliances, fixtures, and equipment. There are many ways to save water in the kitchen. Look for WaterSense and EnergyStar labels, and consider the features described below.

Dishwashers- Residential

residential dishwasherDepending on user behavior and household size, modern, water-efficient dishwashers use less water than washing dishes by hand. Dishwashers can be the most water-efficient option if only operated when full and if dishes are not rinsed before loading. Look for Energy Star and Water Sense labels when choosing a dishwasher. Water-efficient models use an average of only 4 gallons of water per wash, 32-39% less than standard dishwashers, saving up to 1,000 gallons of water per year.

Dishwashers- Commercial

conveyor dishwasherCommercial dishwashers vary in their water use from 2.5 to 8.0 gallons of waterper minute, depending on the type of dishwasher. In a stationary rack machine, the dish racks remain in place whilethey aresprayed with cycles of wash and rinse water. In a conveyor dishwasher, thedishes are placed on a conveyor belt that passes through the machine as dishes are sprayed. The final rinse may include a chemical sanitizing agent that is mixed with water. Most modern dishwashers recirculate the final rinse water and use it for the first rinse of the next cycle.

Garbage Disposals Garbage disposals grind solid wastes into small particles so that they can be discharged into the sewer. The ground garbage passes into a chamber where it is mixed with water for disposal. Garbage disposals generally use 5 to 8 gallons of water per minute, but have a relatively low duration of operation. Most commercial garbage disposals have solenoid valves that shut off the water when the disposal motor shuts off.
Garbage Strainers
garbage strainerReplacing a garbage disposal with a garbage strainer reduces water use by as much as 40%. A recirculating stream of water passes over food waste in the strainer (which sits in the sink's drain) and washes soluble materials and small particles into the sewer, while leaving the large particles to be thrown away in the garbage. The strainer uses about 2 gallons per minute compared to the 5–8 gallons per minute of the commercial disposals.
Plate Cleaning Troughs or Sluice
Commercial kitchens often use scraping troughs or conveyors to remove and carry food scraps and other waste to a garbage disposer before the plates go into the dishwasher. The scraping system uses a trough of water that flows at a rate of 5-15 gpm to carry garbage to the disposer. Conveyors (generally for larger facilities) use water forced through several jets at a rate of 3 - 5 gallons per minute to rinse food particles. Recirculating systems that strain out the solids for disposal and return the water to the trough, reduce water use to 2 - 3 gpm. A cost-effective method that uses no water is to manually scrape food particles into the garbage or a garbage strainer before loading plates into the dishwasher.

Pre-Rinse Spray Valves

rinse smart logoMany commercial kitchens use hand-held or automatic sprayers to remove food particles from dishes before they enter the dishwasher. Older spray valves can use pre-rinse spray valve 3 gallons or more water per minute, while newer, high-efficiency spray valves use half as much or less. The higher pressure of the new valves creates a knife-edge spray, which is more effective at rinsing dishes than standard spray valves. The newer spray valves are rated at 1.15 gallons per minute at 60 psi pressure and can save a medium-size restaurant an average of 50,000 gallons of water per year and hundreds of dollars in energy costs. “Rinse Smart” is the ADWR free pre-rinse spray valve retrofit program.

Refrigerators and Coolers
Commercial refrigerators are usually water-cooled. Older units are often cooled with water in a single-pass fashion, wasting thousands of gallons per day.  New units contain a closed system where a cooling water loop uses a heat exchanger that transfers heat from pipes containing a refrigerant, to pipes containing water. The heat disperses from the pipes by evaporative cooling. Smaller units, such as those found in residential settings, use an air-cooled condenser as their heat exchanger. In natural convection air-coolers the air flows freely over the condenser, cooling the refrigerant inside. Forced convection air-coolers use fans to blow the air across the condenser coils. These systems use no water.
Ice Machines

air cooled ice machineIce machines are water wasters when they use single-pass cooling water to remove heat fromthe compressors and product. An 800 pound water-cooled ice machine uses an extra 1,300 gallons of water each day to cool the condenser. EPA Energy Star models are approximately 15% more energy-efficient and 10% more water-efficient than their conventional counterparts. Flake ice is typically produced on a rotating evaporation drum. Ice is broken off the drum by an ice cutter and scraped to produce flakes that are thin, randomly shaped, and mostly white or cloudy. A typical water-cooled flake ice machine uses 20 gallons of water per 100 pounds of ice produced. Ice cube machines use more water than flakeicemachines because they use warm water to wash over the frozen surface of the cube as it forms. Thewarm water dissolves and carries away minerals and other substances that would make the cube cloudy.This results in clear cubes made of frozen water that is purer than theessource water. A typical air-cooledcube ice machine uses 30 gallons of water per 100 pounds of ice produced and 10-30 gallons two to threetimes a day to purge the system of minerals. Water cooled cube ice machines can use from 72 to 240gallons for every 100 pounds of ice.

Ice cream/Yogurt Machines
Ice cream and yogurt machines are water wasters when they use single-pass cooling water to remove heat from the compressors and product. A typical water-cooled ice cream or frozen yogurt machine uses 2 to 3 gallons per minute (or 1,200 gallons for every eight hours of operation) to cool the condenser whenever the unit is operating. Better alternatives are a closed cooling water loop or an air-cooled model. Air -cooled models use no water. A closed cooling water loop uses a heat exchanger, which transfers heat from pipes containing a refrigerant to pipes containing water. The heat disperses from the pipes by evaporative cooling.
Ice cream/Yogurt Dipper Wells
Dipper wells are used for rinsing and holding ice cream scoopers and other utensils. They typically use constantly running water for sanitary purposes. Low flow systems conserve water, as do hands-free systems that use foot or knee pedals to turn the water on only when needed. Simply turning the flow down or even off during slow periods can save thousands of gallons of water per year.
A combi-oven is an oven with three functions: convection, steam and combination cooking, thereby replacing stand-alone convection ovens and boiler-steamers. In the convection mode, the oven circulates dry heat which is ideal for pastries and breads. The steam mode injects water into the oven to poach fish, rice, vegetables, and other foods. The combi-oven typically uses 9 gallons of water per hour compared to the 40 gallons per hour used by boiler-steamers. Another advantage of a combi-oven is the combination mode, which uses both dry heat and steam to maintain exact humidity levels, providing more control of the moisture levels in food, and cooking food up to 30 percent faster.

Waterless Wok

waterless wok

Conventional woks run water continuously over the stove to prevent over-heating from the accumulated heat under the cook-top. Waterless (or air-cooled) woks allow the hot air to escape from two small air gaps that insulate the wok stove elements. This eliminates the need to use water as a cooling agent and therefore results in a 100% water savings.

Boiler Steamers
Steamers are usually very water intensive, especially the pressureless, boiler-style steamers. Boiler-steamers are connected to a water source and constantly drain water to prevent pressure build-up from the steam. They can consume up to 40 gallons of water per hour, averaging about 175,000 gallons per year. Models with the EPA EnergyStar certification use about 10% less water, or 30 gallons per hour.
Boilerless Steamers boilerless steamerA boilerless steamer (sometimes called ""connectionless steamer"") is much more water-efficient than one that constantly drains water. In a boilerless steamer, the only water used is the amount needed to produce steam. Water is added manually to a reservoir in the bottom of the unit that has its own heating element and is drained at the end of the day. Since there is no connection to a water source, the boilerless steamer uses only about 1 to 2 gallons of water per hour, with a potential water savings of 174,500 gallons per year.