Boring Dishwasher Experiment
Tuesday, January 26, 2010 by Amy
No one will care, but anyway...I seem to have grocery-shopping induced alzheimers, because I have forgotten to pick up dishwasher detergent for weeks now. So, back to washing by hand. This prompted me to figure out if washing by hand is really more water-conserving as I originally thought it was. Well, come to find out that the average full-size dishwasher uses only 3-4.5 gallons of water. So, how much do I use when I handwash? I try to be economical when I handwash, as in, not letting the water simply run as I am rinsing. I fill one sink up for pre-soaking, using 2.5 gallons of water (I measured it!) and I fill the other sink about 2/3 way with water for rinsing, using again 2.5 gallons of water. Right off the bat, I've used more water than my dishwasher uses. When handwashing, I also rinse the dishes. Yes, we rinse as well when washing in the dishwasher, but I am wagering that I rinse less when putting dishes in the dishwasher. I'll even leave that water usage out of the equation so to give handwashing the benefit of the doubt.
Now, I use the dishwasher as a drying rack when I wash by hand, so it is very easy for me to tell that each time I handwash dishes, I can only wash 1/3 to 1/2 the dishes that my dishwasher would be able to hold. Even assuming that I can use one or the other of the sinks-full of water again, I am still using way more water handwashing than using the dishwasher. WAY more. So, 2.5 gallons for one sink, and 1.25 (assuming that I can use one of the sink fulls twice, so 2.5/2) times 2 again (because I wash half the dishes that my dishwasher could wash at once) equals 7.5 gallons of water to wash by hand the same amount of dishes that fit into my dishwasher, which is approximately twice the water used in a dishwasher. Huh!
But, you say, what about the energy that a dishwasher uses? Isn't the water super-heated in a dishwasher? This I cannot calculate on my own, so I turned to this site:
http://1greengeneration.elementsintime.com/?p=314
Turns out, using the dishwasher also consumes less energy. So, dishwasher, I've missed you!!!
Now, I use the dishwasher as a drying rack when I wash by hand, so it is very easy for me to tell that each time I handwash dishes, I can only wash 1/3 to 1/2 the dishes that my dishwasher would be able to hold. Even assuming that I can use one or the other of the sinks-full of water again, I am still using way more water handwashing than using the dishwasher. WAY more. So, 2.5 gallons for one sink, and 1.25 (assuming that I can use one of the sink fulls twice, so 2.5/2) times 2 again (because I wash half the dishes that my dishwasher could wash at once) equals 7.5 gallons of water to wash by hand the same amount of dishes that fit into my dishwasher, which is approximately twice the water used in a dishwasher. Huh!
But, you say, what about the energy that a dishwasher uses? Isn't the water super-heated in a dishwasher? This I cannot calculate on my own, so I turned to this site:
http://1greengeneration.elementsintime.com/?p=314
Turns out, using the dishwasher also consumes less energy. So, dishwasher, I've missed you!!!
