Energy Star Dishwashers - Better than you

Appliances are resource pigs.  In a typical house they consume 60% of all our electricity (assuming non-electrical heating).  It is not surprising then that LEED recognizes homes with more efficient appliances (EA9.1).

LEED provides credits for the installation of Energy Star certified Refrigerators (1 point), dishwashers (0.5 points), and washing machines (0.5 points).  For those of you not familiar with EnergyStar, it is the international rating system to designate energy efficient products.   

In renovating the kitchen we removed the circa 1970s dishwasher and replaced it with a new Bosch Evolution 300 model.  First off, we love the new dishwasher: quiet, efficient and effective.  This is our seventh dishwasher in as many years (we move way too much...) and I would say probably our favourite. 

The 259 kWh annual energy consumption is enough to get the energy star rating and LEED points.  It also officially makes the dishwasher better than me.

In the debate over hand washing vs. dishwasher, this machine has us beat comfortably.  A really interesting study was performed at the University of Bonn in 2004 comparing in detail the dish washing practices of 113 individuals from 7 countries.  What they found was a huge range in washing techniques and styles. In the end though they discovered that to hand wash 12 settings, individuals used an average of 103 litres of water. Our dishwasher uses 14L. 

Overall energy consumption wasn't quite as obvious a difference.  While the dishwasher requires energy to operate, you save energy in the reduction of hot water consumed.  Here the study found dishwashers used 1 to 2 kWh where the hand washers typically used between 1 and 5.5 KWh (one washer actually used 447L of water and 16.6 kWh of energy).  

The end cleanliness of the dishwasher's cleaning was on par with that of the best hand washers as well, leading the closing comments of the study to be "If you can afford a n automatic dishwasher, use one - preferably a new one. A full energy-efficient dishwasher cleans best and has the lowest environmental impact of any method". 

Factor that in with the 500 hours a year they say the dishwasher will save you and I am more than happy to hang up my dishtowel and sponge.