On Fri, 12 Nov 2004 13:42:19 +0000, Paul Burridge
wrote:

The power company run a line to my house. They supply me with
electricity. This amounts to a 230V, 65A facility at the distribution
board in a cupboard under the stairs. I run all my stuff from that
board. The board contains several RCBOs that trip-out in the event of
any leakage current being sensed. If current in = current out; they're
happy and won't trip. Because they don't trip out, I conclude I don't
use any current.
The voltage supplied is 230VAC RMS. Since this is alternating between
equal positive and negative half-cycles, the average level of this
voltage supply is zero.
I use no current and they effectively supply no voltage. Why do I get
billed for electricity usage when I clearly can't have used any?

---
For a purely resistive load, since P = I²R, the sign of the current
going into the load gets squared, so that when it goes in negative it
comes out positive.

For a reactive load, you don't get charged for the imaginary current,
(at least in the US we don't) so you get charged for what you use.

--
John Fields