Energy-efficient Dishwashers Buyers’ Guide

Commercial dishwashers are well known for their high water consumption, often using hundreds of gallons of water per day, which can greatly increase your utility bills and have quite an impact on the environment. These large appliances are also guilty of consuming large amounts of energy, most of which is used for heating the water that will be used to clean and sanitize wares. You can reduce your utility costs and environmental impact by purchasing an energy-efficient ENERGY STAR dishwasher.
How to Choose the Right Energy-efficient Dishwasher
There are two main types of commercial dishwasher to choose from, high-temperature and low-temperature, each with its own "green" benefits.
High-Temperature Dishwashers: There are several benefits to a high-temperature dishwasher that make it an excellent choice for your operation. These units are capable of dissolving difficult-to-clean residue such as grease and lipstick from plates or glasses better than low-temp machines, and they kill bacteria using hot water rather than sanitizing chemicals. Generally, high-temp dishwashers come standard with a booster heater already built in, which can raise the water temperature of the final rinse cycle by 40 to 70 degrees F, depending on the model.
Low-Temperature Dishwashers: Low-temperature dishwashers require the use of chemical sanitizing agents to kill bacteria. The use of cleaning agents eliminates the need for a booster heater, but can complicate the process by requiring chemical refills. Low-temp dishwashers save on energy costs, but the costs of chemicals can offset that gain.
The following chart shows average utility costs for standard dishwashers versus ENERGY STAR dishwashers.
Dishwasher Utility Costs: Standard vs. ENERGY STAR1 | ||||||
Warewashing Unit Type | Average Standard Energy Costs | Average Energy Star Energy Costs | Energy Savings With Energy Star® | Average Standard Water Costs | Average Energy Star Water Costs | Water Savings With Energy Star |
Low Temp | ||||||
Undercounter | $11,254 | $8,647 | $2,607 | $2,071 | $1,634 | 437 |
Door Type | $60,471 | $35,604 | $24,867 | $22,348 | $12,557 | $9,791 |
Single Tank Conveyor | $86,626 | $58,655 | $27,971 | $26,554 | $16,013 | $10,541 |
Multi Tank Conveyor | $102,793 | $64,180 | $38,613 | $31,621 | $16,419 | 15,202 |
High Temp | ||||||
Undercounter | $12,680 | $9,427 | $3,253 | $2,071 | $1,634 | $437 |
Door Type | $61,312 | $43,047 | $18,265 | $13,728 | $9,471 | $4,257 |
Single Tank Conveyor | $93,524 | $74,616 | $18,908 | $17,635 | $14,198 | $3,446 |
Multi Tank Conveyor | $148,765 | $92,504 | $56,261 | $29,493 | $16,419 | $13,074 |
AVERAGE LIFE CYCLE ENERGY SAVINGS: $23,843 | AVERAGE LIFE CYCLE WATER SAVINGS: $7,202 |
1. Data in this table is taken from the ENERGY STAR savings calculator for food service equipment and calculated based on national average energy prices of $0.1032/kWh and $6.98 per thousand gallons of water. Usage is based on 10 operating hours per day, 363 days per year.