Energy Use: The Energy Guide label that comes with every dishwasher shows usage within a scale running from 194 to 531 kilowatt-hours per year (kwh/year). It used to be that 374 kwh/year was good enough for Energy Star qualification, but as of January 1 the threshold was lowered to about 331 kwh/year (based on a complicated formula of percentages and average yearly use). These stricter regulations led many companies to upgrade their products; now many just squeak in at the limit.
Water Consumption: The Energy Star system doesn't take water usage into account, though the government may add that criterion in the future. In the meantime, most Energy Star models use an average of 4 gallons of water per cycle versus 6 for ones that aren't qualified. However, water usage is relative to the cycle you choose, so some can get as high as 8 gallons per cycle even when Energy Star– qualified. One way to conserve water is to scrape dishes and put them right in the machine; that will save 20 gallons of rinse water at the sink.
Energy: 190 kwh/year
Water: 3.5 gallons/load
Smart feature: A load sensor that detects the amount of dishes in the machine; run it half-full and it automatically cuts the water by half.
Approximately $1,599; Bosch Appliances