The most efficient washers use less hot water, have
energy-efficient motors, better spray arms, use sensors
to determine the length of the wash cycle, and have
controls for water temperature. The newest EnergyStarďż˝
dishwashers are 25 percent more efficient than the many
other new dishwashers that do not have the label. At 25
percent, these dishwashers can save up to $25 per year
on energy costs (NRC, 2004). Improved washing action,
spray arms, and nozzles reduce hot water use, and the
energy cost of heating that water. Hot water use primarily
determines the energy efficiency of a dishwasher, so it
is important to choose models that require the least
amount.

Washing cycle times and water consumption vary
considerably between different models of dishwashers
and can be checked by asking to see a machine’s
specification sheet, the instruction manual, or the
model’s use-and-care booklet. A normal heavy-duty cycle,
including drying, can run anywhere from an hour to an
hour and a half. Short cycles run 35 minutes to an hour.
Water consumption varies as well. For some machines,
the water usage is from 8 to14 gallons depending on the
cycle, on others from 6 to 11 gallons. Newer models of
dishwashers are not only more energy efficient than older
models, but they are also better at getting dishes clean.
A relatively new feature found in dishwashers is
electronic touch control panel. These controls offer
options previously unavailable, such as delay-start and
diagnostic features. The delay-start option allows the
dishwashing cycle to begin anywhere from 10 minutes
to 9 hours later. This feature allows owners to take
advantage of off-peak electric rates, run the dishwasher
when there isn’t a high demand for hot water, or simply
when it is most convenient. When purchasing a new
dishwasher, select one that offers different options such
as “low energy option,” “rinse hold cycle,” or “air dry
option.” Look for models with internal “booster heaters”
which permit lower household water heater temperature
settings.

Washing options are very important in a dishwasher. They
may include a low-energy option for moderate to lightly dirty
loads, a regular wash for normal loads, and a rinse-and-hold
washing option. Anytime you use less hot water, you save
energy and money.