I'm looking for an easy explanation for why 220volt service is more efficient than 110. If you have two wet shirts and you place one in a 110v dryer and one in a 220v dryer both rated for the same wattage, why does the shirt in the 110 dryer take longer to dry?
I know you draw less amperage with a 220V circuit but how does this work, why is it more efficient and less costly?

The 220 is not necessarily more efficient. You are drawing a lot more juice. In a 220v dryer you have 110 for the heater and 110 to spin the drum.

In a 110v dryer, that 110v same power does both.

Hello Ecotect:
Lets see "an easy explanation" .....
A 240 volt appliance (usually a motor) is more efficient because it takes less current to get it up to " cruising speed" then a 115v appliance.
The efficiency is short term ( only in the beginning at startup) other then that it takes about the same amount of power to run the motor.
A 240v heating element heats up faster as well.
Thats as simple as I can explain...hope it helps