The efficiency of a dishwasher can be summed up by two factors
The water it consumes.
The electricity it uses.
Thirty five percent of the UK currently use a dishwasher. And per household they use their dishwasher four times a week. Modern dishwashers may not be cheaper than previous machines, but they are consuming less electricity and water.
Therefore if your looking to buy a cheap dishwasher, the initial purchase price should not be your only consideration. With an average dishwasher lasting seven years, an efficient dishwasher with a higher purchase price can save more money over the long term. (update: with more and more machines becoming AAA grade, this is no longer the case)
Aside from the machine, these actions can help you become energy efficient,
Do not rinse your plates before putting them in a dishwasher.
Only wash with a full load in your dishwasher.
Use the low temperature/economic wash cycle when it’s possible.
The ‘Energy Saving Trust’ has the most popular logo found on UK appliances. It denotes a machine which is on average more efficient. A dishwasher with an energy efficient trust logo should save £12 a year on energy bills, compared to a machine without the logo. It is quite difficult to find a dishwasher with a grade of C.
The market place is now dominated by grade AAA dishwashers. Unlike in previous years, when a grade AAA dishwasher held a premium price. It could be said that all dishwashers are now ‘cheap’ when it comes to energy efficiency. Today, noise reduction, build quality and wash programmes seem to be the criteria’s which dictate price.