although i have found numerous sites claiming that automatic dishwashers are the environmental choice, if you look at the research, it just doesn't add up...and many have corporate sponsors who are...you guessed it...the manufacturing companies of the dishwashing machines...

looks like the ecoholic way of dishwashing is to hand wash:
1. wash large sinkloads at a time to conserve water...only fill the sink halfway full for soapy soaking
2. use moderately warm water as opposed to HOT water
3. use a sinkful of water to rinse with rather than rinsing under a running tap
4. use an ecofriendly soap



found the following entry here: www.ecojoes.com/dishwasher...nd-washing/

Let’s say you’re about to clean your dishes, and you want to do it in the best way environmentally possible. So do you use your energy-efficient dishwasher, or do wash your dishes by hand? It might seem like a simple question, but man oh man there are a lot of answers (and a lot of other websites which have covered this question, with one result or the other). I’ll try to look at both sides of this surprisingly heated debate.

Water Use

A modern dishwasher will use less water than you would if you hand-washed your dishes. But this is assuming that you hand wash your dishes several times a day instead of leaving them in the sink for a “big wash”, which I always end up doing. This also assumes that you don’t use too much water pre-rinsing the dishes. So basically, it all boils down to efficiency of scale (doing a large load is more efficient than doing many smaller loads of dishes). If you only do large loads and moderate your water use, hand-washing is more efficient. But the smaller your loads are and the more water you use, the bigger the advantage of using a dishwasher.

Energy Use

Most of the energy for washing dishes (whether by hand or by dishwasher) comes from heating up the water (unless you like to wash your dishes with ice-cold water). Obviously, the dishwasher uses some electricity on top of that, so hand-washing wins this battle.
Time


Overall Environmental Impact

Hand-washing wins this one. There are phosphate-free soaps available for dishwashing or handwashing, but the energy and materials used to make a dishwasher is considerable. Plus, dishwashers take more energy, sometimes use more water, and sometimes even take more time. So unless you are doing a huge load of dishes (or unless you work in a restaurant), then hand-washing is the way to go. So put on them yellow gloves, fill up a pot with hot, soapy water, and get ready for some good ol’ hand-washing.