Quick check in/update!!!
My husband bought a Kill-A-Watt type device a week ago to test how much energy our server closet and gaming computers were pulling, so naturally we've also been testing anything we can get our hands on, including the dishwasher! Yesterday I rigged the dishwasher's power supply with a cord that could be plugged in to the bar above, and connected it to the meter and ran a Normal cycle with no options, where the load was pretty heavily soiled, which meant the usual forcing of three prewashes before the main wash. The device also allows you to key in your energy rates, which for us is $.08 per kWh, and it calculates over time how much it costs to run the particular item over the time it's been in use, as well as displaying watts, amps, and kWh in real time.
I was actually very impressed at how low a power draw this machine uses. Between 35-50 watts at 0.5-0.9 amps for the main wash pump. What was more interesting is that while there is no change in sounds or spraying power, the motor draw would hit the lower 35 or so watts while running the lower arm, and raise typically while the upper was running. Overall, the thing never went above 75 watts/1.1 amps with both drain and wash pumps running at the same time. It wasn't until the main wash that the heating element began running and bringing the display up the ~800 watts.
This is what I found interesting: for the near entirety of the main wash, the heating element would cycle on only while the lower arm was active. As soon as the display fell back down to 40-50 watts, you'd hear the clicking of the diverter, and the upper arm would come on. But contrary to what the "HE trolls" claim, the heating element runs for practically the entire main wash, even with no options selected on a Normal cycle. So to those adamant about new dishwashers using cool water during the wash portion, please, take a seat.
I admit however, this actually surprised me as well. I expected to only see a spike in wattage a few times during the MW, but no, every time the lower arm was active, so was the heating element. I know that it wasn't reaching 135-140 as it would with the final rinse or if HiTemp were selected, but that still indicates that the water is in no way "cool" for wash. During the final rinse, the lower arm spent more time active, which also meant the heater was active longer to hit the target 140F temp.
After the cycle of right at 3 hours, the full power draw was 1.1 kWh, and .09 cents cost in energy, of course not factoring in cost at the water heater, but that would probably amount to a .01 or .02 cent increase. Pretty awesome in my opinion, considering how little water it also uses, and how flawless its results are for every cycle, even the "energy star" cycle. One day I'll try to rig up the PowerClean and do a comparison.