And yeah Anthony, utilities being greedy bastards would be a surprise to
no one. From http://www.generatorguide.net/watt-acpower.html
"In some regions utilities already
installed digital power meters ("smart meters") at the residential level, which
compute
W, VAR, and PF. They may surcharge you for VAR."
*sigh*
Though
I guess in the end it would just make people get more energy-efficient
appliances (and make sure their wiring is clean), which is a good thing
no?
Since as I figured out, my laptop does have a PFC PS (don't
know why I was getting those low PF readings the first time) so then
it's just big appliances which would have the low PFs and thus generate
the additional cost for VAR right?
BINO
> Date: Tue, 2 Aug 2011 12:40:05 -0400
> From: [email protected]
> To: [email protected]
> Subject: Re: [H] PFC (power factor corrected) PS for PCs?
>
> It's easy to budget your VA requirements. Just take the max input
> current listed on all your devices and multiple by wall voltage (~120V
> in the US). That gives you max VA for that device. Do this for all
> devices you plug in and add them up. Buy your UPS for that total.
> You're guaranteed to be covered, but you will likely have some margin
> too if you don't always draw max current.
>
> If utilties start charging residential customers for additional VARs, it
> will be because they are greedy bastards.
>
> On 8/2/2011 12:28 PM, DSinc wrote:
> > Bino,
> > OK. You win! Yes the AC voltage you measure at the wall plug is 0.707
> > (rms) of the peak AC sinusoidal wave-form (169.731V) when viewed via
> > an o-scope. My comment was with regards to your concern about KWh and
> > KVA values. In your apartment you spend your dollars buying AC power
> > measured in Watts not KVA.
> >
> > Yes, have read about these new digital 'smart' residential
> > watt-meters. I have one on my home now. And I fully expect that in the
> > future (as my AC Service provider completes it's 'Smart Grid'
> > technology) I may see my bill change based on 'time of day' power
> > usage during peak demand (system wide) situations.
> >
> > Yes, it is confusing in the UPS calculation game. All of my UPS's are
> > rated at 1500KVA. Yet, they also will only supply a maximum output of
> > 875 watts continuous.
> >
> > I do not follow your points about 'VA' rating of a device. If it plugs
> > into your wall plug it is spec'd in watts.
> > My understanding about Power Factor and/or Power Factor Correction
> > technology is some form of quantifying electrical efficiency. IMHO. I
> > leave area to the those that understand. I do not. Yet I do agree that
> > our modern PSU's are very much more efficient AC to DC converters.
> > Sorry to interject skepticism into your search for truth.
> > Best,
> > Duncan
