why does a 3/4 hp aircon consumes more than 746*0.75=560 watts?

oz93666

Joined Sep 7, 2010
737
sure they have.... just not for consumer market. consumers have very small loads and don't pay penalties for imbalancing grid
A search shows this is not the case ... domestic users pay unnecessarily too much if they are not balanced ,,, Many companies selling devices to domestic users

panic mode

Joined Oct 10, 2011
1,916
they also sell Bigfoot and UFO detectors, snake oil and miracle cure for anything...

maybe there is an honest product in that group but from what i have seen so far, all of consumer grade products are just a junk.

Like 50KVA device size of a bar of soap with cable no bigger than #AWG18 is sold for $12-50. Me thinks that 50KVA on a single phase (even if for 230VAC) should handle quite some current that shown connectors and cables are not able to handle by a long shot. And at low frequency (50-60Hz) capacitors would need to be quite large. if you find one that is actually reasonable and maybe even work (and automatic, not just fixed capacitor bank) please share your finding. Maybe we are looking at different products or we are not equally skeptic about world around us. Btw, my electricity bill is nothing compared to my monthly spending on things like coffee, gas etc. i am pretty sure PFC in my household would not save the planet even if some crazy politicians... Political statement removed by a moderator -no politics please. Last edited: oz93666 Joined Sep 7, 2010 737 they also sell Bigfoot and UFO detectors, snake oil and miracle cure for anything... maybe there is an honest product in that group but from what i have seen so far, all of consumer grade products are just a junk. Like 50KVA device size of a bar of soap with cable no bigger than #AWG18 is sold for$12-50. Me thinks that 50KVA on a single phase (even if for 230VAC) should handle quite some current that shown connectors and cables are not able to handle by a long shot. And at low frequency (50-60Hz) capacitors would need to be quite large.

if you find one that is actually reasonable and maybe even work (and automatic, not just fixed capacitor bank) please share your finding. Maybe we are looking at different products or we are not equally skeptic about world around us.

Btw, my electricity bill is nothing compared to my monthly spending on things like coffee, gas etc.
i am pretty sure PFC in my household would not save the planet even if some crazy politicians are Political statement removed by a moderator -no politics please.
You are missing the point ...domestic meters charge the consumer based on current , not power ....IF TS figures are correct , and if he were to uses his AC 10 hrs a day , he could save $100s /year just by adding some capacitors . WBahn Joined Mar 31, 2012 26,398 You are missing the point ...domestic meters charge the consumer based on current , not power ....IF TS figures are correct , and if he were to uses his AC 10 hrs a day , he could save$100s /year just by adding some capacitors .
The overwhelming majority of residential meters (in the U.S. -- it may well be different in other countries) are real-power responding. They have both voltage and current sensing coils that the meter moves in proportion to the instantaneous product of the two. If the current and voltage are 90° out of phase, the meter won't move (on average).

If the meter only looked at the current, then there would be no way to do net-metering for customers that feed power back to the grid. The direction of energy flow isn't determined by the current, but by the phase relationship between the current and the voltage.

panic mode

Joined Oct 10, 2011
1,916
exactly

oz93666

Joined Sep 7, 2010
737
Exactly what ??? I think some people here just post whatever they think ... no back up

All the searches I've done on this show consumers do pay excess for un-balanced loads and many companies are selling devices to domestic consumers to correct this ...

Please supply links to back up your position ... I'me not even sure what this is since it's already agreed SOME countries charge , perhaps TS is from one of these countries

panic mode

Joined Oct 10, 2011
1,916
true but i tried not to call you out:

if you find one that is actually reasonable and maybe even work (and automatic, not just fixed capacitor bank) please share your finding. Maybe we are looking at different products or we are not equally skeptic about world around us.
here is my power company. call them if you don't know what kW, or kWh is:

how do you backup your claim that 0.76HP load can save $100's annually? using what compensation exactly? Last edited: oz93666 Joined Sep 7, 2010 737 ....how do you backup your claim that 0.76HP load can save$100's annually? using what compensation exactly?
I was careful to say if figures given by TS are accurate ....

He has told us he is measuring power consumption with a meter "used it in a shop i once rented". presumably the type of domestic meter used by power supplier to charge customer ... this meter shows 'nearly 1000W' with this 560W AC , so by adding capacitors it should be possible to get this same meter to show 560W consumption ... saving 400W every hour ...$100s /year. WBahn Joined Mar 31, 2012 26,398 Exactly what ??? I think some people here just post whatever they think ... no back up All the searches I've done on this show consumers do pay excess for un-balanced loads and many companies are selling devices to domestic consumers to correct this ... And just where is the backup that you've been providing for your claims? Please don't provide any results that are claims made by companies that sell residential power factor correction devices. These are almost always snake oil and of course snake oil salesmen are going to make all kinds of claims about how their snake oil is going to save you money. Please supply links to back up your position ... I'me not even sure what this is since it's already agreed SOME countries charge , perhaps TS is from one of these countries Where was this agree to? I said that I didn't know and that some countries might -- that is NOT saying that any countries actually do. Here's some to back up what I've stated: https://en.wikipedia.org/wiki/Electricity_meter Specifically: "Electricity meters operate by continuously measuring the instantaneous voltage (volts) and current (amperes) to give energy used (in joules, kilowatt-hours etc.). " Not that any bill that is for kWh is a bill for REAL POWER (or energy, to be precise). If they are billing for apparent power the bill will be for kVAh and if they are applying a surcharge of any kind they will be noting the reactive power, kVARh, it is based on. I looked at quite a few utility web sites trying to find one that billed residential customers for apparent power or made a surcharge for excessive reactive power. I wasn't able to find a single one (which is not to say that they don't exist). ALL of them discussed power-factor and how it affects their BUSINESS customers. Virtually none even mentioned power factor on their residential pages because it is a non-factor since it doesn't affect the bill (directly -- since they have to cover their costs it does affect the bill indirectly because the reactive power causes real losses in the distribution system and so that loss is built into the rate charged for real energy). Here's one that did mention it directly: https://www.duquesnelight.com/account-billing/understanding-your-bill/business-bill/power-factor "Note: if you only have single-phase service there is no need for you to read any further. Power factor penalty does not apply to single-phase service." Notice that this is on the business side. They have a page dedicated to what affects residential billing https://www.duquesnelight.com/accou...ll/residential-bill/what-is-affecting-my-bill Note that not one word is mentioned about power factor. Here's an analysis: https://www.powerelectronics.com/power-management/power-factor-correction-justified-home Not only do they state: "Utilities may assess commercial or industrial customers a penalty for PF significantly less than one." But their analysis of residential savings is based on the actual cost of the increased REAL POWER consumption in the home caused by under-unity power factor (primarily increased joule heating of the wiring in the home because of the higher currents, which is the same mechanism that accounts for the bulk of the cost of reactive power to the utility company). https://thegrid.rexel.com/en-us/kno...ic-utility-bills-with-power-factor-correction "In residential buildings, these types of loads are minimal, so residential electric rates typically ignore power factor. " https://electronics.stackexchange.c...her-residential-customers-about-power-factors https://www.edn.com/electronics-blo...Can-they-really-reduce-your-electricity-bill- "However it is important to note that utilities bill a residential user based on real power that does not factor in Power factor and thus none of these devices would really reduce your monthly bill. " Let's see what NIST has to say: https://www.nist.gov/news-events/ne...ifies-utility-power-factor-correction-devices https://ws680.nist.gov/publication/get_pdf.cfm?pub_id=903669 "However, the homeowner’s electric bill will not decrease because, as noted above, the cost is determined in part by the product of current, voltage, and power factor." panic mode Joined Oct 10, 2011 1,916 use of AC is highly seasonal.... for start lets say it is used 3 months in a year and it is running 24/7 during those times. 3 months * 30 days/month * 24h/day = 2160h 2160h * 0.75kW = 1620kWh say your electricity cost is$0.1 / kW, so your annual bill is $162... if this runs non-stop. but in reality, AC is not running 24/7, 100% duty cycle. so this is probably fraction of mentioned figure. Now explain to me, how is someone PAYING for something additional, going to save$100's a year when annual bill is less than $100 to start with? based on my estimate (see calculation), the only way to save that kind of money is to turn this AC unit off. well open switch is technically a tiny capacitor, wired in series with load and already built in so no extra cost and therefore no need for additional expenditure on some scam product. i am still waiting to see your link to a product that is residential, measures power factor and automatically switches capacitors in to get OPTIMAL correction. and it need to be affordable so that our unit saves$100's annually

i checked my power meter and electricity bill. both mention kW and not kVA. i am dying to see ones in kVA.

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WBahn

Joined Mar 31, 2012
26,398
use of AC is highly seasonal....

for start lets say it is used 3 months in a year and it is running 24/7 during those times.
3 months * 30 days/month * 24h/day = 2160h
2160h * 0.75kW = 1620kWh
say your electricity cost is $0.1 / kW, so your annual bill is$162... if this runs non-stop.

but in reality, AC is not running 24/7, 100% duty cycle. so this is probably fraction of mentioned figure.

Now explain to me, how is someone PAYING for something additional, going to save $100's a year when annual bill is less than$100 to start with?
based on my estimate (see calculation), the only way to save that kind of money is to turn this AC unit off.
And not to mention that the majority of air conditioning units already have a power factor compensation capacitor built in. Doing this for circuits such as this is easy and reasonable since the power factor when running is pretty constant. Doing it properly for an entire house whose power factor is constantly changing is a lot more difficult -- unless of course you are selling snake oil.

panic mode

Joined Oct 10, 2011
1,916
There are many "products" of thins kind, with varying degree of complexity but all have one common thing - they only exist to make money by deceiving gullible:

it was sad to see youtube video of some kid in a 3rd world country (India?) showing how to build this thing.
then he bravely tries to save energy of a RESISTIVE load (iron). 1200 likes, 23k subscribers. (facepalm)

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crutschow

Joined Mar 14, 2008
28,158
Exactly what ??? I think some people here just post whatever they think ... no back up
domestic meters charge the consumer based on current , not power
All the searches I've done on this show consumers do pay excess for un-balanced loads
So list one of those searches as backup.
Domestic where?
Not in the USA.

shortbus

Joined Sep 30, 2009
8,952
There are many "products" of thins kind, with varying degree of complexity but all have one common thing - they only exist to make money by deceiving gullible:

it was sad to see youtube video of some kid in a 3rd world country (India?) showing how to build this thing.
then he bravely tries to save energy of a RESISTIVE load (iron). 1200 likes, 23k subscribers. (facepalm)

But you do get a free EMF hood with them.

oz93666

Joined Sep 7, 2010
737
"...The power utilities in most industrialised nations charge users a penalty when their power system’s power factor drops below a certain level, usually below 0.90. This power factor surcharge covers the electric utility’s cost of supplying your power system with additional reactive power.
In South Africa, no “fines” are imposed as yet, although Eskom intends...." https://alphapowersolutions.co.za/faq/

People are missing the main facts here .... TS obtained his meter "from a shop he used to rent" ... we can assume this is a domestic powersuply meter typical of those used in the country he lives in ...

It's showing "nearly1KW" on a 560W AirCon unit ... Is it not reasonable to assume this could be due to powerfactor , that his present domestic grid meter will also register nearly 1KW and charge him for a KW ??

Less Hot Air/theory needed ....Put some capacitors in parallel and see what happens!

WBahn

Joined Mar 31, 2012
26,398
"...The power utilities in most industrialised nations charge users a penalty when their power system’s power factor drops below a certain level, usually below 0.90. This power factor surcharge covers the electric utility’s cost of supplying your power system with additional reactive power.
In South Africa, no “fines” are imposed as yet, although Eskom intends...." https://alphapowersolutions.co.za/faq/
That company makes power factor correction equipment for medium to large industrial and commercial installations and that statement is referring to the billing of such installations.

Since you seem to believe that the information from that company is reliable and acceptably authoratative, let's see what they (the company that YOU are using as your information source) has to say about domestic power factor correction:

Can power factor correction reduce electricity costs in a domestic residential environment?

No, the addition of power factor correction may reduce the current drawn by your residence, but this will not result in a reduction of your electricity costs. This is due to the fact that you are only being billed for your active power consumption (kWh) and not for maximum demand (kVA) nor for your reactive power consumption (kVArh).

Power factor correction in a residential application is primarily only used to prevent the main incomer circuit breaker from tripping by reducing the total current drawn. The power factor correction panel supplies most of the reactive current drawn by the inductive components in your residence, and in so doing, reduces the total current flowing through the incomer circuit breaker.

There is no financial benefit in doing so, there is only a “comfort” benefit.