Here in San Diego, I'm currently borrowing a "check meter" from the power company. The check meter is simply a standard electrical kwh meter with a plug on one cord and an outlet on the other. You plug the meter into the wall and the appliance into the meter.
So far, I've found that my fridge is using only about $9 of power a month while my hot tub is using $45 - $50 of power.
Ask your local power company about a "check meter".