While you should choose your washing machine very carefully when energy and water use are your prime considerations, the story is different for dryers. Despite the many brands and sizes on the market, they differ very little in terms of energy use. This is why you'll find that dryers do not carry the Energy Star label. A dryer typically ranks second, after refrigerators, in terms of the amount of energy you use in your home. As it stands, electric dryers are responsible for 5 to 10 percent of a home's electricity usage.
But there are still things you can do! For one, look for dryers with a moisture sensor setting, which can reduce the drying time. The sensor detects how much moisture is actually left in the clothes and will turn off the machine when moisture is gone, rather than waiting for a predetermined amount of time to pass. Most new models come with this feature, making your shopping job easier.
Developers are working on new machine-drying technologies, but not much has hit the market. Until a greener machine option is available, it's best if you use your dryer as little as possible, though when you do use it, do so efficiently.