When it comes to reducing our water usage, we have some moves down pat: shut off the water while brushing teeth, install a toilet that uses less water per flush, and wait until we’ve got a full load for the washing machine, for example.
But what about washing dishes? In terms of saving on water, is it better to wash by hand or to use a dishwasher? On the one hand, there’s the running water or the full sink (and do dishes get clean in a sink full of dirty dishes anyway?). On the other, there’s the dishwasher that sounds like it’s running forever.
Turns out dishwashers are a pretty economical way to go. According to CNET, an Energy Star certified dishwasher can use as little as three gallons of water per load, while cleaning them in the sink can use up to 27 gallons. Pay attention, though: a dishwasher built before 1994 can use more than 10 gallons per load.
Newer dishwashers have heaters built in that warm up water more efficiently than a hot water heater, which can also cut down on energy costs. And you don’t need to rinse them beforehand. Scrape off the big stuff and leave the small stuff alone; no need to wash before you wash.
One last note: as with the washing machine, wait until you have a full load or all calculations are skewed. Use an extra rinse cycle if you must wait a while before you have a full load.