Here is what Energy Star has to say about dryers:
- All dryers use about the same amount of energy.
- The most energy efficient method is of course the clothes line.
- Having a washer with a high-spin cycle will result in dryer laundry going into the dryer, which can save energy.
You can also use the moisture sensor on your dryer and go for options that don't dry as much (which at our house results in few wrinkles too).
Also, clean your lint trap and make sure your ducts are clean to save energy.
For more information:
Read "What brand of washer/dryer would you recommend? We want low-maintenance, energy efficient and Energy Star compliant." a Q&A answered by Kristina Hahn.