老巫：洗碗经济学

洗碗机洗一次碗用电、煤气：$0.13 - $0.18

洗碗机洗一次碗用时：10分钟

手洗一次用水：25加仑

手洗一次碗用电、煤气：$0.16（2度电，每度$0.08）

手洗一次碗用时：30分钟

 

结论

自己去算吧。

 

课外阅读

This is still a hotly debated topic, despite the number of studies done at Universities and other testing facilities.

Studies have "proven" that modern dishwasher uses only half the energy and one-sixth of the water, with cleaner results. This could be due to the fact that the optimal temperature for cleaning washing is 140 degrees, which is too high for most human hands. Or the studies could be biased by sponsorship of some appliance manufacturer. Also omitted these studies are the amount of energy it took to build the dishwasher itself, plus transporting it to the various distribution points.

Regardless of the studies, there are many factors involved which may tilt the balance. For example, dishwasher requires a full-load. But if you wash a glass or plate immediately after using it, you may require very little water as the food is not yet stuck to the plate. Some people may even reuse the water for their plants, making the water savings hard to beat. Of course, some cultures run the water constantly while they wash their dishes...

But if you have a large family and a perfect load after each meal, it may be difficult to beat the dishwasher.