William Sommerwerck wrote:
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.

That's VARs, not VA-hours. For 'volt-ampere reactive'.

If you can have watt-hours, you can have VA-hours. Both are units of energy.

Is VAR a unit of energy? No, it's a unit of (reactive) power. Energy and
power are not the same.


Yes, of course. But a VA-hour is a meaningless unit unless you know the
power factor--real power costs money and fuel, whereas (apart from
transmission losses) reactive power just sloshes back and forth cycle by
cycle. That's why multiplying it by any period of time longer than a
cycle is meaningless.

Cheers

Phil Hobbs

--
Dr Philip C D Hobbs
Principal
ElectroOptical Innovations
55 Orchard Rd
Briarcliff Manor NY 10510
845-480-2058
hobbs at electrooptical dot net
http://electrooptical.net