Now that you mention it, it sounds like a good idea. From a European perspective, taxing electric usage made by heating, cooking or watching TV differently seems right.
I was under the impression that electricity is not very taxed in the US, while here it is.
Also we have different tax rates for different things. You don't pay the same tax for eggs than for electronics. I don't know if the US has that. Applying the same to electricity sounds good. Hard to implement though.