gavra
just to be a touch more precise:
I believe the following is true, I would like someone to confirm it.
The Chazon Ish holds completing a circuit is boneh. Not electricity itself.
The nafka minah I believe is that if no electricity is currently flowing into your house (say a local outage), it would still be assur to flick a switch on or off (al pi boneh, not just muktza).