Depends on the voltage standard in your area. If it's "only" drawing 24 watts that means you're running it in 120V North America. In other places that use 220V like Europe it's going to take 44W.
If this was the case, why would anyone use 220v over 110v, you pay your electrical bill based on the KwH consumption which is directly related to the wattage, it would be cheaper to get a step-down transformer and run everything at the lowest voltage possible.
As Haqqs mentioned, electrical engineering is complicated, electricity consumption on the other hand is rather simple, if it says 1000w on the label and assuming it's accurate, it will always print 1000w on your meter regardless of the voltage, the voltage will affect the amps (lower voltage = higher amps).
But if you are interested in calculating the amps (which is pretty irrelevant for this case) I = W / V where I is the current in amps, W is the wattage and V is the voltage, so if something consumes 220w on a 220v circuit, it will draw 1 amp, if you run it on a 110v it will draw 2 amps (220/110 = 2), but of course this is sort of oversimplifying the subject to give you the general idea.