This is an interesting topic.
The trouble with the "cheaper" argument is that as noted before: watts = volts * current
Imagine that the hairdryer in a previous example draws a maximum of 550 Watts .. that would be 5 amps on 110v and 2.5 amps on 220v. Still the same amount of energy .. just different variables
This is why the power company bills in Watts and not Amperes
