HeyBub wrote:


Heh! KW-hour meters measure resistive loads. Since inductive loads have the
same phase displacement as resistive loads, inductive loads (like AC
compressors) also are accurately measured by a KWH meter.


Inductive loads have reactive and resistive components. The current is
not at the same phase angle as resistive loads. KWH meters measure the
true power, whether the load is pure resistance or includes inductance
or capacitance.

Reactive loads are NOT detected by a KWH meter. Placing the right sized
capacitor across an inductive load phase shifts the load into a reactive
load which IS invisible to a KWH meter.

*Pure* reactive current (capacitor or inductor), at 90 degrees, is not
measured by a KWH meter. A pure reactive load does no usefull work.

An inductive load is already a reactive load. Adding capacitance across
an inductive load will decrease (not increase) the effective reactance
which increases the power factor and lowers the line current (if not
over corrected). The KWH meter measures the true power whether the
inductive load is PF corrected or not.


So there's some truth to the claim. I don't think you can turn a pure
resistive load (like a light bulb) into behaving like a reactive one (on the
other hand, CFL have a transformer...).


There is no truth as you explain it. If you add pure inductance or
capacitance to a light bulb the KWH meter will still measure the true
power consumed by the light bulb.

CFLs are more efficient in converting electrical energy to light energy.
Transformers result in an energy loss.

Power factor correction can save a lot of money where a utiltiy measures
and charges a penalty for reactive power (like industrial). There will
be metering for both true power (KWH) and reactive power (KVAR). It
shouldn't affect demand, which is based on peak true power.

Correction can also lower the current *slightly* which lowers the
resistive losses in the wire. For metering, the losses are only reduced
in the wire from the meter to the PF correction capacitors. In a house
this is negligible. And correction would have to vary to match the
inductive load that is connected or else the circuit would be over
corrected and the current would be raised.

As almost everyone said - it is a scam.

--
bud--