Re: Power saving unit?

["Ian Lowe" <ianlowe@xxxxxxxxxxxxxxxxx>]

--- In ukha_d@xxxxxxx, Vargster <vargster@...> wrote:
>
> I think this http://www.powergard.ca is similar tp
the one that appeared on
> the BBC news website.
> Any chance it might sctually work then? And thereby save on the elecy
bill?
>
> Lee

I'm sure one of the electricians can explain this better, but it seems to
be trying to alter the power factor - which is a 'fake' measure of your
consumption..

power factor is a hound of a thing to explain...

basically the power numbers you would get in a DC environment, where simple
rules like power = voltage * current hold true, and the AC world are
different.

AC voltage traces out a sine wave - the current flowing in the circuit also
follows a sine wave.. what's a little counterintuitive is that the current
and voltage sine waves are not always in sync.

if your circuit only contained simple components with just resistance the
current and voltage would be in sync.

As soon as you add inductance and capacitance into the circuits, then the
current and voltage slip out of sync... and the calculation of the true
power consumed becomes more complex - and the ratio between your
theoretical Volts * Amps power, and the *actual* power being consumed is
your power factor.

Power meters make assumptions about your power ratio, as do electricity
providers - devices like this may reduce a bill in the short term (bt
almost certainly not by much - a few percent tops), but they won't affect
the actual amount of power being used in any real sense: the same amount of
coal/gas/whatever will need to be used to generate the same amount of juice
- it will just read differently on the meter in your premises.

If this is pants, please - I'd welcome a better explanation from someone
who relaly 'gets' power factor. I always feel that my understanding is a
bit tenuous...





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