On Mon, 2 Nov 2009 14:13:27 -0800, "William Sommerwerck"
wrote:

Your electric meter measures watts, not VA. If you know the power
factor, you can convert these VA measurements to watts and eventually
to your cost of electricity. The kill-a-watt meter shows both VA and
watts (as well as PF).

My understanding was that the watt-hour meter actually measure VA-hours. I
asked the electric company once, and that said that was the case. But I
wasn't speaking with an engineer.

I beg to differ. If it measured volt-amps, it would say volt-amps,
not watts.

See:
http://en.wikipedia.org/wiki/Electricity_meter
"Demand is normally measured in watts..."
and:
"Modern electricity meters operate by continuously measuring the
instantaneous voltage (volts) and current (amperes) and finding the
product of these to give instantaneous electrical power (watts) which
is then integrated against time to give energy used (joules,
kilowatt-hours etc)."

http://www.generatorguide.net/watt-acpower.html
"Note that residential meters only measure only real power (watts) and
PF of your appliances do not affect your cost of electricity".

Note that some utilities charge extra for low power factor loads:
http://www.envido.co.uk/what-we-do/power-factor-correction

Marginally related but interesting drivel:
http://www.google.org/powermeter/

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558