lgolara
Member
Hello,
We are working with a small designer who has six sewing machines. This is the biggest part of her electricity bill and we are looking at ways to help her reduce her bills.
Does power factor correction work on a small scale? For example,could it be used on her sewing machines and if so would she see a benefit in her electricity bills? We have heard alternate theories about if it would or wouldn't work on a small scale.
Thank you,
LG
ghostgum
Member
My understanding is that the distribution company metering measures real power (not apparent power), and that small consumers are not penalised for poor power factor.
If you want to check the power factor, buy or borrow a meter such as
http://shop.ata.org.au/cart.php?target=product&product_id=16630&category_id=322
If it is 0.9 or above, then I wouldn't worry.
What is more interesting is to leave this meter on an appliance for 24 hours and to measure how much power it uses.
Yes, power factor does work on a small scale. I should put PF capacitors in some of my fluoro lights, but it isn't going to make any difference to my bill.
alfresco24
Member
There's no reason not to apply it to sewing machines, if your tests show there is an issue.
Does the client actually get billed on a power facter corrected (KVAR) basis?
Most small consumer and businesses don't, so there would be no point in adjusting it.
How 'bad' is the power factor?
The classic example of small scale power factor correction is the fluro light fitting where if it wasnt for the power factor capacitor the light wouldnt appear to consume much power according to the meter.
If you're game to experiment, the easy way to do it is go find some old fluro fitting and take out the PF capacitor, connect it across your 240V motor, and retest. Settling on the right value of capacitor depends on how 'dirty' your inductive motor is.
Solgen
Member
As others have mentioned it depends on what tariff she is on. If she is on a standard kWh tariff then no need to put in power factor correction. However, if she is on a demand tariff where she pays for the max kVA demand each billing period plus kWh used then power factor correction would be an option.
alfresco24
Member
Solgen has a good point.
All smart meters have power factor or KVAR(reactive power) measurement ability. Whether it's enabled/reported or not is another story.
It has been the case that all contestable customers under 160MWh are/were not subject to KVAR adjustment as long as it was above ~0.85PF (depending on which state & distributor you're with).
However I have personally seen domestic users billed for KVAR where their KVAR usage was 'extreme'. So beware, it is possible to be billed if you have a 'smart meter' and you PF falls too far below 0.87PF
