Dishwashers are classed as “wet’ appliances. Dishwashers switched to the new A to G energy rating scale in 2021, when there were too many A+++ models on the market for consumers to tell the difference. Today, there aren’t that many A-rated goods on the market yet, so look for a C and D-rated appliances which are more energy efficient than those with an E or F rating.
Dishwashers are set to heat water to between 60 -63 degrees C and can use between 1.5 and 6.5 gallons of water per cycle. and but can actually be re-set to heat to a maximum of 49 degrees and still clean perfectly well. The least water is used on the economy (eco) program. This washes dishes at lower temperatures and with less water. On average, economy programs use 30% less energy and water compared with the main program. However the dishwasher stays on for three hours or more which can deceive people into thinking more energy is being used.
On the subject of using less water, don’t be tempted to rinse your plates before putting them in the dishwasher. Just scrape leftovers into the bin. Washing dishes in hot water by hand actually uses more energy than a loaded dishwashing cycle, and you will also save 55 gallons of water if you let the dishwasher do its job.
Only run a cycle when the dishwasher is full, but not overloaded. If you have a delay or timing feature then start a full load late at night, or early in the morning when the cost of power is less, and even if the cycle is slow, it will be clean and ready to unload at breakfast. The residual heat of the dishwasher can also help heat a low ceiling room so cutting heating bills.
Don’t use the drying mode. Baking dishes in hot air once they’ve been cleaned is an unnecessary use of energy. So open the dishwasher door as soon as the cycle is finished and air dry to save more money.