Electricity costs about 10 cents per KwH in local currency, thats about 4 cents US per KwH and thats mostly generated from renewable energy sources [like Hydro, some Wind].
We don't have any Nuclear power plants.

The cost about 23 cents was from the 'promotional guff' the manufacturer put on the packaging.
Not sure how they calculated it, maybe there is some kind of power factor involved.

My point was that the device cost far more the buy than cost of the power it used.