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Discussion Starter · #1 ·
Anyone familiar with KVAR Energy Devices?

Recently while researching ways to save energy I came across a Phoenix, AZ local Fox News video at this link:


A 70% reduction in energy required to power a refrigerator goes a long way in an off grid system. But I get the impression that a whole house 220volt unit would only save energy on 220 volt motors and compressors and not the 110 volt appoliances as shown in the news story. I have found the demo models also for sale for less than $200 I think it wsa.
 

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Not familiar with that system ... I might have to look a bit deeper into it ..
 

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Most of the bigger loads in your house are inductive motors. That will bring down your power factor. Most meters account for your power factor and bill you extra accordingly. A capacitor on your system can cause your power factor to shift toward the center. You want to keep your power factor as high as possible. 1.0 is maximum. If your loads are capacitive, a KVAR unit would cost you money.

I'd be careful about Power Factor Correction equipment for residential use. It may be something that you would only want to turn on when you AC is in use. You can use a harmonics analyzer to determine your power factor, but since your load changes, so does your power factor. I wonder if I should experiment with putting a capacitor on the load side of my compressor input contactor. That would shift the power factor toward unity(assuming your load is inductive), but you would think that this was considered in the design of your AC or any other high dollar appliance with an inductive motor. (dish washer, washer, dryer, ceiling fan, refridgerator, etc...)

Bottom line: Check it with a harmonics annalyzer if you can before you add capacitors to your house wiring. Find out if the KVAR automatically switches on and off as needed or if it is just a dumb capacitor.

This explains it better than me. The discussion below helps also.

http://powerelectronics.com/power_management/motor_power_management/power-factor-correction-0507/

If your meter measures real power and not apparent power, PFC is a waste of time and money. That's what you need to find out first.
 

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Discussion Starter · #7 ·
Good information Tex. That explains a lot. I seriously doubt the unit has automatic switch and would lead to higher untilty cost.
Thanks!
 

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Power companies take this into account when they bill you. You're billed for the KW hours you use not the KVAR.

If you draw a triangle one leg will be KW (real power that does work), another leg will be KVAR (Reactive power, power that is stored in magnetic fields as in capacitors or inductors. this power is returned to the source but tends to increase the actual electricity running through the lines). The hypotenuse of the triangle will be KVA (Killovolt Amps Apparent which is the actual amount of electricity running through the lines).

The above poster is correct in that a power factor of 1 is considered unity and all power is real power and is the ideal situation. If your home has mostly motors or inductive loads you will have some power factor less than 1 and current will lag voltage by some angle depending upon how far away from unity you are. If you have more capacitive loads you're power factor will be less than 1 but current will lead voltage depending upon the same criteria cited above.

These devices may make your power factor closer to 1, but the power company won't care because they have ways of determining exactly how much real power (KW) you are using and you are billed accordingly.

Sorry, I don't have a less technical way of explaining this. There's an explanation on wikipedia if you look up "power triangle"

BTW, large manufacturing facilities that consume massive amounts of electricity do sometimes use setups to improve their power factor, but it's mostly to reduce the size of the wires feeding the places due to the extra electricity flowing back and forth due to reactive loads that don't do any actual work.
 

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Power companies take this into account when they bill you. You're billed for the KW hours you use not the KVAR.

If you draw a triangle one leg will be KW (real power that does work), another leg will be KVAR (Reactive power, power that is stored in magnetic fields as in capacitors or inductors. this power is returned to the source but tends to increase the actual electricity running through the lines). The hypotenuse of the triangle will be KVA (Killovolt Amps Apparent which is the actual amount of electricity running through the lines).

The above poster is correct in that a power factor of 1 is considered unity and all power is real power and is the ideal situation. If your home has mostly motors or inductive loads you will have some power factor less than 1 and current will lag voltage by some angle depending upon how far away from unity you are. If you have more capacitive loads you're power factor will be less than 1 but current will lead voltage depending upon the same criteria cited above.

These devices may make your power factor closer to 1, but the power company won't care because they have ways of determining exactly how much real power (KW) you are using and you are billed accordingly.

Sorry, I don't have a less technical way of explaining this. There's an explanation on wikipedia if you look up "power triangle"

BTW, large manufacturing facilities that consume massive amounts of electricity do sometimes use setups to improve their power factor, but it's mostly to reduce the size of the wires feeding the places due to the extra electricity flowing back and forth due to reactive loads that don't do any actual work.
FINALLY! A voice of reason!

I run into these things around once in a while, and people SWEAR they are saving this or that...
Until you get the bill comparisons from the utilities and they find out it's the same as it always was...

A solar install got shut down because of one of these things because the city inspector didn't know what it was and though we had installed it...

Much better money spent plugging up air leaks, insulating attic and doors, around windows, ect.
Switching to CF or LED bulbs is always instant money in the bank!

Just did my sister's house last year in Texas, just outside Austin.
CFs, plugging up leaks, insulating the attic, ect.
Cost was about $1,500 and took me a week, but I'm lazy and slow...
40% reduction in energy bills alone for the 7 months since she's been able to track it...
 

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Old thread but since I own one...

I have one. I payed ~$400 for it. I've had it since December. Last month I received my lowest power bill ever since living in this house (circa April 2004). This month we have the AC running which is the big power hog. No numbers on that front yet but I will post results once they become available.

I can add that the motors in the house act noticeably differently since the unit was installed. We have 4 ceiling fans that are on constantly and they seem to be a quieter and move more air at the same speed setting. The fridge and dishwasher seem quieter as well. Small things, I know.

My highest power bill was in August of last year. After sending the power company a check for $450 I started looking at anything that could lower the bill.
 

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I have one. I payed ~$400 for it. I've had it since December. Last month I received my lowest power bill ever since living in this house (circa April 2004). This month we have the AC running which is the big power hog. No numbers on that front yet but I will post results once they become available.

I can add that the motors in the house act noticeably differently since the unit was installed. We have 4 ceiling fans that are on constantly and they seem to be a quieter and move more air at the same speed setting. The fridge and dishwasher seem quieter as well. Small things, I know.

My highest power bill was in August of last year. After sending the power company a check for $450 I started looking at anything that could lower the bill.
You've been scammed

Read This. It pretty much mirrors my previous post
 

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Kvar 1200

Anyone familiar with KVAR Energy Devices?

Recently while researching ways to save energy I came across a Phoenix, AZ local Fox News video at this link:

YouTube - Fox 10 News Report On KVAR Energy Savings Device

A 70% reduction in energy required to power a refrigerator goes a long way in an off grid system. But I get the impression that a whole house 220volt unit would only save energy on 220 volt motors and compressors and not the 110 volt appoliances as shown in the news story. I have found the demo models also for sale for less than $200 I think it wsa.
Yes the unit does work with 110volt.....199 is a really good price. I was the exclusive sales rep for Guelph, Ont in 07..and beleive me its a fantastic technology. However, what is not so great, is the fact that as always it takes consumers forever to catch up with it. We were promised that are hydro supplier was going to offer billing direct to there monthly statement in easy installments of course...because then i was selling them for 699 pl tx.! Im not sure youll find to many DEMO models out there for that price at least not in canada. In fact i think i have the only one left which i posted on kijjiji for 199. cheers jamie
 

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Yes the unit does work with 110volt.....199 is a really good price. I was the exclusive sales rep for Guelph, Ont in 07..and beleive me its a fantastic technology. However, what is not so great, is the fact that as always it takes consumers forever to catch up with it. We were promised that are hydro supplier was going to offer billing direct to there http://en.wikipedia.org/wiki/USS_Augusta_(SSN-710)monthly statement in easy installments of course...because then i was selling them for 699 pl tx.! Im not sure youll find to many DEMO models out there for that price at least not in canada. In fact i think i have the only one left which i posted on kijjiji for 199. cheers jamie
KVAR or more correctly var is a measure of the volt-amp-reactive component of power. It is "imaginary power" in that is does no work nor is consumed. It is however stored in magnetic fields such as produced by inductive loads (motors, solenoids, or other such things that use inductors) and capacitive loads. Note that I said "stored" and not "used". All reactive power is returned to the source (generator, electrical grid, etc) at a rate of 60 times per second (in the US) and therefore not used. (it is not considered real power which is measured in Watts. The only way this device could possibly save money is to reduce the heating of the electrical wiring used to furnish appliances in a home. This heating I would say amounts to less than 1% of the electricity used in a typical residential home.

Industrial facilities such as mine that routinely use 120K Amps per steel melting furnace (we have 2 operating about 80% of the time) do benefit because this amount of electricity would generate excessive heat which would be wasted energy or facilitate us using cabling that is several times larger than what we can use if we limit the reactive power. If I remember correctly, we spent somewhere in the neighborhood of $600k on a unit to reduce the amount of reactive power, but that's justifiable when our electric bill is north of $4M a month.

Residential use = Scam. They provide no benefit as the electric companies charge you in actual power used (KWH) not in (KVA or Kilo-Volt-Apparent which takes into account the KVAR, reactive power)

Off the grid = Scam. Unless you're trying to reduce wire size and I wouldn't think this would be necessary since off the grid systems typically don't use very much power.

Another note; These do nothing for DC systems as KVAR only applies to AC systems.

If anyone wants to purchase one, by all means go ahead, but you'll only be wasting your money by giving it to someone else and gaining nothing useful in return.

I'm an electrical engineer (not saying that gives me credence), I've never studied these commercially available KVAR devices, but have been involved in industrial models and do understand the effects of KW, KVAR, and KVA on a distribution system.

from wikipedia said:
Engineers use the following terms to describe energy flow in a system (and assign each of them a different unit to differentiate between them):
Real power (P) - watt [W]
Reactive power (Q) - volt-amperes reactive [var]
Complex power (S) - volt-ampere [VA]
Apparent Power (|S|), that is, the absolute value of complex power S - volt-ampere [VA]
In the diagram, P is the real power, Q is the reactive power (in this case positive), S is the complex power and the length of S is the apparent power.
Reactive power does not transfer energy, so it is represented as the imaginary axis of the vector diagram. Real power moves energy, so it is the real axis.
The unit for all forms of power is the watt (symbol: W), but this unit is generally reserved for real power. Apparent power is conventionally expressed in volt-amperes (VA) since it is the product of rms voltage and rms current. The unit for reactive power is expressed as VAr, which stands for volt-amperes reactive. Since reactive power transfers no net energy to the load, it is sometimes called "wattless" power. It does, however, serve an important function in electrical grids and its lack has been cited as a significant factor in the Northeast Blackout of 2003.[1]
Understanding the relationship between these three quantities lies at the heart of understanding power engineering. The mathematical relationship among them can be represented by vectors or expressed using complex numbers, (where j is the imaginary unit).
 

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believe the salesman, not the electrical engineer.

These devices are scams, they provide no useful benefit to the residential customer or any other small scale systems. They only provide benefits to large industrial companies who can be charged penalties by the electric companies because of their effect on the power factor of the entire grid.

Entire neighborhoods have negligible effects on grid power factor, but you claim that this device will save a considerable amount of money.

from article said:
Finally, lets assume you run a wash every day of the year (perhaps true if you have children). Annual power cost: $0.00438
This is the savings you would achieve if you mounted the device at the washing machine (which by the way, these aren't whole house devices. By their very nature they have to be mounted by the appliance. You would have to have one by your washer, refrigerator, AC unit, basically any load you're looking to save money.

You will never regain the cost in your lifetime.

Other sites
Do Power Factor Correction Devices (kVAR) really save money? This is the EnergyStar Site
has anyone tested a KVAR unit? - Electrical Wiring Forum - GardenWeb
KVAR PFC Unit - Scam Review | open4energy
Power Factor scams -- Ask Mr. Electricity
 
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