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Power-Save Power Factor Correction Capacitors
 

 

Subject - Power-Save Power Factor Correction Capacitors

June 25, 2007
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Power-Save Power Factor Correction Capacitors

 

 

Electrical Engineer Heinz Rosen recently contacted us in response to our new myth-busting efforts. He has been looking into power factor correction capacitors sold by Power-Save.

Original E-mail from Mr. Rosen: I've been looking into power factor correction capacitors sold by Power-Save and touted for residential use to save lots of money. They've recently gone into an advertising blitz on TV and mailings. You can find them on the web at www.Power-Save.com. To support their claims they prominently feature a University of Santa Clara Report written by a couple of Ph.D. Professors.

I had quite a few problems with how the product is used, the claims made for it and, in particular, with the University Report. I wrote to the President of the Power-Save (the only contact I was able to find) and questioned a number of assertions. Several of the University Report’s claims are questionable and some technical explanations dubious if not downright wrong, the explanation of the service connection, however, is scary in its ignorance and danger. Below is a copy of the letter.

March 12, 2007

Mr. Michael Forster,

President and CEO

Power-Save

3940-7 Broad St. #200

San Luis Obispo, CA 93401

 

Subject: Power-Save 1200 Questions

 

Dear Mr. Forster:

 

This letter is addressed to you because we were not able to locate any other customer contact individual to whom our questions could be directed.

 

Several families in our neighborhood saw the ad for Power-Save and being interested in saving money by reducing our energy expenses requested your brochure. After reading the brochure and the information provided on the Power-Save web page (http://www.power-save.com/), including the Santa Clara University report (Click here for report), certain questions arose. It would be appreciated if you could have someone provide answers to us before we commit to purchasing the Power-Save 1200 and having it installed in our homes.

 

For ease of reference the questions are listed below.

 

General Questions

1. To the best of our knowledge, based on information received from utilities, residential watt-hour meters measure KW-Hours not KVA-Hours. KW (dissipative) loads are independent of any reactive loads that may also be on the circuit. Since the homeowner only pays for KW-Hours how does improving the power factor reduce the KW-Hour charges to the homeowner?

2. Assume that the homeowner does pay for KVA-Hours. All inductive loads in a home are on only intermittently. The capacitive Power-Save 1200, however, is connected continuously. When few or none of the inductive loads of the home are on what prevents the power-factor from becoming negative (capacitive) and increasing the KVA demand from the utility compared to what it would be if the Power-Save were not connected at all during that time?

 

3. The brochure refers to the Power-Save 1200, the university report talks about the ABET 2201. How does one model relate to the other?

 

4. Power factor correction capacitors are normally rated in KVARs. There is no mention of the KVAR rating of the Power-Save 1200 either in the brochure or on the web. What is the KVAR rating of that model?

 

Questions Specific to the Santa Clara University report by Ayhan Mutlu, Ph.D. and Mahmud Rahman, Ph.D.  Quotation marks surround sections quoted from the report. Our questions are in dark blue.

 

"3.1. Power Factor Correction. ABET-2201 brings the advantages of the power factor correction capacitor to household use. Figure 1 shows a typical connection of the ABET unit in a household. This unit is usually connected to the fuse panel where the electricity is distributed to different locations in the house. As mentioned above, the current passing through the current coil of the Energy-meter installed by the power distributor to monitor power consumption is the algebraic aggregate of the individual resistive, inductive, and capacitive currents flowing in different loads of the household, as shown in Fig. 1. Since the currents flowing in inductive and capacitive loads are half a cycle out of phase, it is possible to make their sum zero at any particular time by adjusting their magnitudes, consequently reducing the total current magnitude flowing through the Energy meter."

 

5. The authors seem to be unaware that most watt-hour meters measure just that, not the product of current and voltage. Although reducing power factor has beneficial effects for the utility by reducing line losses and potentially reducing distribution transformer sizes, there is no benefit to the rate-payer to improve power factor. What are we missing?

1

Fig. 1. An example ABET-2201 installation in a typical household.

 

"Due to the reduction in the total current, the power loss (I2total x R1) in the resistance R1, between the wattmeter and the ABET-2201, which varies from house to house, is also reduced. This is the instantaneous power saving that is achieved by installing the ABET-2201. It is important to note that i) the resistance R1 will depend on the locations of the Energy-meter and ABET-2201, and ii) the power saving is proportional to the square of the reduction in the current brought about by the ABET-2201.

 

Figure 4 presents average voltage, current, power, and power factor measured over a period of one hour in an actual household. It is clearly observed that the power consumption is reduced along with the improved power factor and reduced current."

6. Similar comment as in 5. However, the discussion concerning the power loss in R1 is relevant since it contributes to the KW load (paid for by the rate-payer.) See further discussion of this in question 7c.

 

2

 7. There is no indication where the measurements represented in this figure were made. Presumably at the service connections after the energy meter shown in Fig.1. Nonetheless, some issues arise:

a. Since the inductive loads are intermittent and the power factor correction is continuous just what does “average” mean in connection with Q and power factor of Fig. 4? If it is the traditional meaning of the time integral of the function divided by the relevant period then it would not be applicable to the situation at hand. It is possible to choose a capacitive load that “on average” yields a power factor of 1.0 but since the energy measurement occurs continuously and the power factor alternates between some value between 0 and plus 1.0 and 0 and minus 1.0 there would be no or little reduction of the “average” current demanded from the utility, resulting in no or little savings to the rate-payer. Would you please comment on that?

 

b. From Figure 4 it might be deduced that the capacitive load of the ABET 2201 is implied at 1.347 KVAR (1773-426 VARS.) on the assumption that the inductive load is on continuously. However, this is not the case and when the inductive load is off there would be a 1.347 KVAR capacitive load, reducing the power factor and again increasing the current demand from the utility. The Figure(s) and text are unclear about exactly what measurements were made. Would you please comment on that?

 

c. Fig.4 shows a reduction of 36 W in actual power usage, attributing that result to a reduction of I2R losses in R1. Let us look at this more closely. An average single-family residence is generally provided with about a 150 A single-phase service. According to the NEC copper conductors for such a service are required to be AWG. No.1 minimum. The resistance of AWG No. 1 copper is 0.16 Ohms/1000 ft. The distance between the meter and the main panel rarely exceeds 50 ft. Thus the total distance for hot and neutral conductors is  about 100 ft for a total resistance of 0.016 Ohms. A reduction of current from 10.66 A to 7.63 A calculates to a reduction of 0.146 W loss in R1. Where do the 36W come from? Once again the Figures and text are unclear. Would you please comment on that?

 

"Our experiments have shown that adding ABET-2201 has reduced the peak inrush current of the tested motor by about 5%. Also, when the motor was under full load, the unit has reduced the inrush current time about 15%."

3

 

8. Where were the motor inrush current measurements made? While it is true that a motor starting from stand-still has a high inrush current no theoretical reason is offered to explain why placing a capacitor across branch circuit terminals will reduce that inrush. Although a capacitive shunt at the input will reduce the transient seen on the supply conductors it is the capacitor (if it were large enough) that provides the energy for the inrush current which will remain the same as before. Let’s look at that a little closer. From the Fig. 4 implied 1.347 KVAR capacitive load it is simple to calculate the capacitance as 64μF. At 236 V this capacitor holds an average charge of 15x10-3 Coulombs. For a motor inrush current of 40 A. (Fig. 5) that amount of current is not even enough to sustain one mS of surge. We would appreciate an explanation of why the ABET–2201 reduces the motor inrush current.

 

Furthermore, Fig. 5 seems to show that even the running current of the motor is reduced when the ABET-2201 is installed. There is no mention of that in the text. We would appreciate an explanation of that, as well.

 

"This behavior of capacitors have lead to applications where these are connected in parallel with the power circuits of most electronic devices and larger systems (such as factories) to shunt away and conceal voltage and current fluctuations from the primary power source to provide a "clean" power supply for signal or control circuits. Such effects in capacitors can also be interpreted to act as a local reserve for the DC power source, …"

 

9.We don’t understand the comment about capacitors “…can also be interpreted to act as a local reserve for the DC power source…” What DC power source? If what is meant are the various DC power supplies integral to the various electronic equipment that may be in a home and that are connected to the branch circuits in the usual way, these contain their own built-in transient filters and surge suppressors. Could you please offer further explanation?

 

"The ABET-2201 in conjunction with the resistance of the household wiring forms a low-pass filter which prohibits higher frequency components from the incoming supply into household loads. Consequently, motors are subjected to less heating as illustrated in Fig. 7. "

 

4

10. While it is true that the 0.016 Ohm R1 and the 64μF ABET-2201 form a low pass filter we do not understand why the house wiring plays a role in that filter. Once the frequencies in question have reached the ABET they would propagate throughout the branch circuits unless there are other shunt capacitors (or series inductors) in the circuit. The house wiring would play a role if there is a capacitor directly across the motor but that would exist even without the ABET-2201. Thus we need to examine the low-pass filter formed by R1 and the ABET-2201. The “corner” frequency, f0, of that filter, that is the frequency at which the amplitude is reduced to half, can easily be calculated as 146 KHz! Every frequency below that will pass into the branch networks at nearly the same level as it enters the panel. Certainly the effect of that filter on the first several harmonics of 60 Hz. would be minimal.

 

Since there was no information provided in the report about the measurement of the harmonic content before and after installation of the ABET-2201 could you please provide us with some information concerning these measurements and a detailed explanation why the report shows the reduction in motor operating temperature and attributes this (without explanation) to a harmonic content reduction?

 

"4. The power distribution panel installed by distributor

The distributor of electrical energy installs a power distribution panel outside a household so that their personnel can monitor the total energy consumed by the household by reading the Energy meter installed in the panel. Two wires with 220 V across them are brought in from the locality supply grid into the distribution panel. All loads in the house which run on 220 V are connected across these two wires. Loads which run on 120 V are connected across one of these two wires and the ground terminal which is fabricated in each household by inserting a solid copper rod deep into the soil. All 120 V loads are divided into two circuits, each consisting of one the above mentioned two wires and the ground terminal. Figure 8 shows these two different configurations."

 

 

5

"Fig. 8. Distribution panel configurations in a household"

 

11. We had serious problems with this paragraph. To begin, the symbols used in Fig. 8 are totally different from the standard ones used in plans and there was no legend explaining the symbols, either in the text or in the figures. Therefore it was impossible to determine what is connected to what.

Single phase power distribution to residential homes is almost exclusively 120/240V provided by a center-tapped transformer secondary winding. The secondary winding carries 240V end-to-end while each end is 120V to the center tap. The center tap is the white neutral conductor that is connected to the neutral bus in the panel. The two black wires are connected to two power busses in the panel. Although grounding is a part of every safe distribution system it plays no part in routing the return current back to the source.

 

The text makes no explanation of how loads connected between the hot leads and ground rods without any additional connections or circuitry derive 120V from the 220V (sic) wires, the only ones that the text mentions as being brought from the utility. There is no mention of a return path. A distribution system such as described in the text would not work, would be unsafe, and would be in violation of the National Electric Code, that forbids using the earth as a return path.

 

We are surprised and baffled by this section.

 

We are prepared to purchase and install the Power-Save units once we have received satisfactory answers to our questions and look forward to your reply.

 

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Comments
  • Sigh. Those of us with training and education and experience with electricity will continue to strive to save "true believers" from "snake oil." But, all of our words will never change a mind. True Believers have too much at stake to consider that science, physics, and engineering may prove their belief "wrong." The truth is available for anyone willing and interested. Sadly, there is so much "dis-information" available, true believers can always find "proof."

    Mike Beanland
    Reply to this comment

  • I still have not heard from anyone as to the Value uf of the capacitor or capacitors utislized in the Powersave 1200 can anyone help.

    Paul Markham
    Reply to this comment

  • Following is a summary of a report I prepared recently on "Enersonic Power Saver" units. Sorry it's a bit long! Even though we expect they should not save power in theory, I

    thought it is reasonable to test them anyway. I'd've been both surprised and delighted to find their claims true. Enjoy...

    Enersonic Power Saver units were tested ... in order to determine whether they meet claimed performance. The headline claim is Saving power = Saving money + Saving the environment Potential Power savings up to 24%.

    Our test results dispute that claim.

    The Enersonic Power Saver was found to behave as one expects a power factor correction capacitor should: it can reduce the current and increase the power factor when connected in

    parallel with an inductive load. However, domestic electricity consumers in Australia are not changed on the basis of current or power factor; indeed there is no means of

    recording current or power factor with domestic metering. Rather, domestic consumer charging depends on the active power and these units do not reduce the active power nor the

    consumer’s bill. Equally, they do nothing for the environment.

    There is no reasonable prospect of achieving the order of 24% reduction in the domestic user’s electrical power under any practical conditions that the author can foresee with any

    number of units.

    The promotional material represents that the goods have a performance characteristic and a benefit that they in fact do not have which may breach the [Australian] Trade Practices

    Act 1973 Sect 53.

    Lab Tests We tested two inductive loads (unloaded transformers and "Vacmate" industrial cleaner AC motor) with and without the power saver units connected.

    Load voltage current power power saving saving volts amps watts factor watts % transfo 246.6 0.64 33 0.214 induct tr+1EPS 246.4 0.25 33 0.552 induct 0 0.0% Vacmate 245.6 3.59 847 0.967 induct Va+1EPS 245.7 3.46 846 0.981 induct 1 0.1% Va+2EPS 246.3 3.53 848 0.977 capacit -1 -0.1%

    The results show that connecting the Enersonic Power Saver gives no measureable saving in power. This can be seen by the “saving” columns. The saving is zero, within the +/-1 watt

    measurement accuracy.

    Domestic Test The overall household power consumption was measured at the author’s house (what I imagine to be a fairly average house). The electrical loads included inductive loads:

    fluorescent lights, electronic equipment on standby, plug-packs, television, radio etc. The active power was measured with 0, 1, 2, 3 and 4 Enersonic units connected in random

    order. We monitored the energy E [kW.hr] consumed over a convenient period of time t [sec]. The average power was calculated by P = 3600000E/t. We also monitored the voltage V

    [volts rms]. To be a fair test, the voltage needs to be constant. If the voltage measured with a particular load varied by more than +/-1% during the procedure it was deemed an unfair test and

    was repeated. All testing was repeated several times to verify the measurement repeatability. Repeated measurements were averaged.

    Units voltage power saving saving volts watts watts none 236.3 394.3 1 233.0 391.4 3 1% 2 236.0 396.3 -2 -1% 3 234.0 397.3 -3 -1% 4 236.0 397.1 -3 -1%

    The results show that connecting the Enersonic Power Saver gives no measureable saving in power. This can be seen by the “saving” columns. The percentage saving is virtually zero.

    The small measured variation in power (+/-3 watts) probably arose from small variations in voltage and power drawn by appliances that occurred from time to time during the test.

    Ron Bradbury Technetium Design (Australia)

    Ron Bradbury
    Reply to this comment

  • Following is a summary of a report I prepared recently on "Enersonic Power Saver" units. Sorry it's a bit long! Even though we expect they should not save power in theory, I thought it is reasonable to test them anyway. I'd've been both surprised and delighted to find their claims true. Enjoy...

    Enersonic Power Saver units were tested ... in order to determine whether they meet claimed performance. The headline claim is Saving power = Saving money + Saving the environment Potential Power savings up to 24%.

    Our test results dispute that claim.

    The Enersonic Power Saver was found to behave as one expects a power factor correction capacitor should: it can reduce the current and increase the power factor when connected in parallel with an inductive load. However, domestic electricity consumers in Australia are not changed on the basis of current or power factor; indeed there is no means of recording current or power factor with domestic metering. Rather, domestic consumer charging depends on the active power and these units do not reduce the active power nor the consumer’s bill. Equally, they do nothing for the environment.

    There is no reasonable prospect of achieving the order of 24% reduction in the domestic user’s electrical power under any practical conditions that the author can foresee with any number of units.

    The promotional material represents that the goods have a performance characteristic and a benefit that they in fact do not have which may breach the [Australian] Trade Practices Act 1973 Sect 53.

    Lab Tests We tested two inductive loads (unloaded transformers and "Vacmate" industrial cleaner AC motor) with and without the power saver units connected. The results show that connecting the Enersonic Power Saver gives no measureable saving in power. The saving is zero, within the +/-1 watt measurement accuracy.

    Domestic Test The overall household power consumption was measured at the author’s house (what I imagine to be a fairly average house). The electrical loads included inductive loads: fluorescent lights, electronic equipment on standby, plug-packs, television, radio etc. The active power was measured with 0, 1, 2, 3 and 4 Enersonic units connected in random order. We monitored the energy E [kW.hr] consumed over a convenient period of time t [sec]. The average power was calculated by P = 3600000E/t. We also monitored the voltage V [volts rms]. To be a fair test, the voltage needs to be constant. If the voltage measured with a particular load varied by more than +/-1% during the procedure it was deemed an unfair test and was repeated. All testing was repeated several times to verify the measurement repeatability. Repeated measurements were averaged.

    The results show that connecting the Enersonic Power Saver gives no measureable saving in power. The percentage saving is virtually zero. The small measured variation in power (+/-3 watts) probably arose from small variations in voltage and power drawn by appliances that occurred from time to time during the test.

    Ron Bradbury Technetium Design (Australia)

    Ron Bradbury
    Reply to this comment

  • Sixty plus years ago, I invented a wonderful machine. My dad had a pretty extensive shop and I piddled around in there a lot. I rigged up an old starter motor. Belt driven, to my go cart. Found a good battery and the thing would haul me around until the battery ran down. So, my answer was to fashion an old generator and voltage regulator driven by the wheel on the other side. I was so proud. My dad said “let me know how it works out. You will learn a valuable lesson” Of course that is exactly what happened. You cant use less electricity than you are really using.

    Fred
    Reply to this comment

  • Here\'s a thought: The power companys have almost unlimited resourses. They are billing you for electrical work. If there was a device that could fix it so you paid for less work energy than you consumed, doesn\'t it seem logical that the poco\'s would be concerened? Over the years there have be some gadgets sold that would actually slow or stop your meter. They were illigal and some folks that were prosecuted for using them. Stick wit more efficient appliances and lighting if you want to save on your electric bill

    Fred
    Reply to this comment

  • Whoa! There seems to be a lot of confusion about this subject. I am an electrical test engineer and start power plants up for a living.

    1) Once and for all, the power company does NOT charge you for reactive power. The meter on the side of your house is KWH meter, and reads KW only. The utility does NOT charge you VARS. Correcting your power factor will NOT reduce you KW demand.

    2) What does correcting the power factor do? It increases the energy efficiency at the source (in short). That would be the generator! Yes, you will see many factories and even the utility use power factor correction capacitors on the line in order to reduce VARS and increase power factor. But...the factory does not decrease their demand as a result. A factory will install them for one of two reasons. 1- to receive a credit from the utility. 2- to avoid penalties from the utility for poor power factor. But the utility does not penalize residential customers for power factor. Nor will they give you a credit!

    3) I went to the Power-Save website and watched their video. This is what I saw. In their example of a typical installation they start with the unit off and you have the following data shown on the their power meter: KW: 0.502, KVA 1.069, KVAR 0.935, and a PF of 0.473 When they turn their unit on their meter shows the following: Yes a PF of 0,857 but they draw your attention to the PF reading on the meter only as if you were stupid and try to dark out the other readings...which are KW 0.497, KVA 0.597, and KVAR which is 0.297. In essence they have acheived increasing the power factor which is great for the utility company because you are actually saving them money on the generation end... but if you notice you still have the same KW. Of course your overall KVA and KVAR's have gone down because you have decreased you have improved your power factor. Unfortunately the utility charges you for KW only and not KVA.

    Hope this helps.

    Informatively yours,

    William

    William Johnson
    Reply to this comment

  • A friend of mine with absolutely no experience in the electrical field has just paid for a "distributorship" of KVAR Energy Controllers. I believe she can sell both residential and commercial, but had to purchase residential units to become a distributor. She has told me that for commercial use, an individual will fly in to size the load and they will build the correctly-sized commercial unit. From what I read here, the only real use for these units is commercial, and may possibly even pose unknown danger to residential users. Here is a link to their website, anything different about this unit for residential use than the others mentioned in this thread?

    Lori
    Reply to this comment

  • I just e-mailed and realized that I forgot to add the link to the KVAR Entergy Controller, here it is

    http://www.kvarenergysavings.com/

    Lori
    Reply to this comment

  • Greetings to all. I am actually looking into a PFCD as we speak and am told that it has 2 capacitors in it that would "recycle" the Kvar back into the circuit allowing a few things to happen: 1. The appliance has an outlet for the wasted energy created thus allowing it to run cooler. 2. Since the energy is "recycled" back into the unit, the need for additional energy is reduced thereby lowering you Kw hours used. I am not an electrician but this makes sense. Am I wrong in my assumption? Thank you for your help!

    Juan Ramirez
    Reply to this comment

  • Like a bad penny, like a good scam, and like a nasty rumor, they just never go away. What amazes me is the number of "engineers" who do not understand the physical reality. I have to remind myself that "engineers" come in all flavors and grades. Some are "A" grade and their clear, supported, and articulate statements should be believed. Some "engineers" are "C", "D", or "F" grade and just add to the confusion and mis-information.

    Mike Beanland
    Reply to this comment

  • The response labeled number 7 subparagraph C debunk in very clear summary that the device sold is misrepresented. The math does not lie. The I2R loss would be as demonstrated by the de bunker, .146 watt and not 36 watt as the seller of the device claims. This is a good example of the terms whole truth and nothing but the truth. While technically the addition of the device can result in a reduction (very very small) in I2R losses it can not significantly reduce the kwhr consumption. Considering possible side effects and cost the device is similar to bitters medicine sold before our nation took a stand against quackery medicine cures.

    Walt
    Reply to this comment

  • Assuming anyone is still checking this thread.... a couple of questions. I just stumbled upon the power save website and in the course of researching it found this site. The power save website appears to have been updated since Heinz sent his original letter. Did Heinz (or anyone else) try the toll free number or the email address posted on the site to get these questions answered? Did Heinz (or anyone else) contact the authors of the paper at the address posted on the title page of the article? It seems to me that one would start there rather than writing the CEO of a $65 million company. Scam or not, he may have more to do than answer individual letters. Another site has a post from a "... Past President of Ga. Hospital Engineers Society" and his conclusion is that the device will work. URL: http://askville.amazon.com/Answer-Past-President-Ga-Hospital-Engineers-Society/AnswerDetails.do?requestId=4574892&responseId=4621200

    KP Smith
    Reply to this comment

  • Dear Sir,

    I am looking for the answer of following question:

    1. I would like to run AC armeture (motor), which generates 15 KW of electricity, by DC motor or dynomo powered by car batteries. The RPM of AC motor is 1450 and has to produce 220 volt, my question is what should be the capacity of DC motor in Horse Power and how many car Batteries of 12 volt are required to run the AC motor to generate 15 KW (220Volt) of electricity?

    Sarad Shrestha
    Reply to this comment

  • In addition to the capacitors, they are also now pushing a "revolutionary" new wind generator that exceeds the absolute possible Betz limit even for a perfect wind turbine.

    So not only do their capacitors defy the laws of physics, but so do their wind turbines.

    Windsun
    Reply to this comment

  • I just finished reviewing the entire chain and would like to know what happened to Bruce? The discouraging thing for us folks in the capacitor business is the never ending barage of snake oil salesman and the electrically uneducated that witness the amp-probe demonstration and believe it to be relevant to kW. Thanks for the original letter to the CEO, Heinz.

    Gus Zobel
    Reply to this comment

  • thank you all for your comments, i am definitely not buying one of these gizmos. i am not a PE or really very familiar with how electricity works, however i have a refrigerator that burns out a motor at least twice a year. I am trying to find a solution to this problem and based on advertisements this Power Save seemed to be a solution. I am thinking of buying a new refrigerator, but i am not sure that will solve the problem. Any idea on what i should look for as the cause?

    Bonnie
    Reply to this comment

  • Useless? Yes. But dangerous too?

    It may be interesting that the very same snake oil is now marked in Australia by Harvey Norman, one of the largest and most successful homeware chains. It's called an Enersonic Power Saver. This plugs in to a power outlet and is then connected all the time. If one were to pull it out of the outlet the PF correcting capacitor may be charges to as much as 240*1.414 = 339 volts. Touching the pins on the unit will delivery an electric shock.

    A small capacitance will not produce a dangerous shock but a large capacitance can. How large is dangerous?

    I see that posting here has been quiet for some time. I hope that someone is listening!

    Ron Bradbury
    Reply to this comment

  • Can we look at this from a different angle?

    I am a contractor with experience in installing and using capacitors (commercially). I am not defending any product, but I am pointing out that capacitors CAN be good and MAY "indirectly" save money.

    Say everyone agrees that a capacitor "Can" improve a power factor, "IF" there is room for improvement and its the right capacitor. FACT: All power companies and electrical utilities use capacitors to improve "power factors". They sit next to transformers at power substations. My Grandfather was a high power lineman, back in the 1950's for Ohio Power, and they used them back then too. To keep it simple, a good "power factor" is good, not bad.

    We also know that an improved Power Factor "alone" will not reduce the WATTS (KW) that a running motor uses, only the Amp draw (KA) from the power source. As an example of saving Amps and not saving watts; a 110v/220v motor that uses 5 amps at 110v, only uses 2.5 amps when running at 220v. That saves "Zero" on the wattage. And that stays the same regardless of the "power factor". BUT the Power Companies / Utilities can and some do, charge you extra $$ on your electric bill for having a BAD power factor going in to your home. Again, To keep it simple, my point is a good "power factor" is good, not bad AND you improve power factors with capacitors.

    NOW, If the "power factor" is improved in the home, doesn't that help motors run more efficiently in the home? (running less to get the same job done, and / or run with less heat output?) That is why they are used in factories and large refrigeration storage facilities too.

    If an improved power factor does, even in a small way, improve how efficient a motor runs, then a refrigerator or air conditioner would run less often to cool the same, right? Because it is using power more efficiently and is running at a lower temperature. (common sense = if an air conditioner "air handling fan motor" is running "less hot", the air conditioner does not need to work as hard to negate the heat generated by the motor. And by the motor running less hot, it MAY extend the life of that motor. Heat is BAD for motors). Therefore using less "wattage" or KW (and KA for that matter) to run, because it runs "less often". And "in theory" you will have to replace that motor "less often" because it is running more efficiently and has less "wear and tear" on it. Both saving money. Right?

    Then improving the power factor is an "indirect cause" of KW savings not a direct one.

    Another Example of my point: In order for your Refrigerator/Freezer to get an "Energy Star" rating (see www.energystar.gov), from the Government, it must have two motors and a capacitor. "Energy Star", a Federal Government Program, will then "RATE" the "Savings" of using that appliance verses one without a capacitor (i.e. your old one, which may already have two motors). The appliance manufacture then charges on average 30-40% more for the appliance with a capacitor and an "Energy Star" Logo next to the yellow sticker on it saying the rate of "savings" or "payoff" over "X" number of years. They do the same for Air Conditioners too (regarding capacitors).

    I am not defending Power-Save sales people or any other product, but I am pointing out that the Government is encouraging appliance manufactures and consumers to use capacitors to "save money". It looks like a capacitor could indirectly save you money (how ever big or small) in your home. If you are charged KVA, like most business are, then there would be a greater savings, right? This doesn't look like "snake oil" in this situation. It just looks like uneducated people are selling capacitor systems for the wrong reasons. If presented fairly, with the RIGHT facts, capacitors are not EVIL, only sales people that are UNEDUCATED and misrepresent the fundamentals of electricity.

    The bottom line is, if it saves you money (directly or indirectly) and pays for it self in less than 5 years, GREAT!, if not, ask for your money back!

    Comments?

    p.s. all capacitors slow down or "suppress" surges naturally.

    Douglas Paul
    Reply to this comment

  • The attorney general needs to get involved before:

    1. Peoples hard earned money is stolen by these thieves 2. Some one is injured, or worse killed, by this shameful twisting of reality

    Melvin P. Dolittle
    Reply to this comment

  • Fact : watt-hour meters only read watts which is true power. At the power company I work for we have volt-amp meters, volt amp reactive meters, and watt-hour meters. If your house only has watt-hour meters then what you use in your house only measures that value. Therefore you can't save money by increasing power factor, you will only save the power company at the source by letting them only produce the current necessary to provide you with your clean watts. End of story.

    bruce crubel
    Reply to this comment

  • What I find fascinating in this thread, is the fact that you all are willing to live in a theoretical world; nothing is based upon empirical observations of the device in question. Please get off of your thesis mentality - acquire one of these things, test it in the field and then pontificate. You speak of snake oil salesmen: "So are they that hide behind formulas and riddles without the benefit of true observation. " At this point, you are all carnival barkers. Speaking loudly with conviction, no matter your lack of proof. Pity. Have fun with your mental master......!

    Bruce
    Reply to this comment

  • Clearly, you have a bias and an agenda. My comments are being blocked. Talk about snake oil. I say "Skunk". Good day to all ye sheep. Let your mentor watch over, blind and shear you.

    Bruce
    Reply to this comment

  • Bruce, I find it hard to believe that you are so incensed by the comments here, unless you have a dog in this hunt. Tell us. Are you peddling these devices?

    Fred Madden
    Reply to this comment

  • As long as there is a scam to be worked, there will be unscrupulous people trying to dupe the innocent. The challenge of informing people is really demonstrated here as shown by the confusion of those who should be knowledgeable. The subtlety of KW-Hrs and KVA-Hrs is not easy for a consumer to grasp - even trained engineers are confused. I visited a foreign Utility who complained that their capacitor bank had no effect on system improvement. Turns out they had located it on the first pole outside their generator (Benefit accrues to 50 feet of their 10 mile feeder) and put their current sensors on the downstream side of their bank! (Couldn't measure the effect of turning the bank on1) This from professionals! In addition to advising the University of the gross errors of reports sent out under their Letterhead, this is blatant enough to be fodder for 60 minutes, many regional consumer advocates and local investigative reporters. Our alert should be presented in terms a lay person can understand. (Not an easy task)

    John Angelis, P.E.
    Reply to this comment

  • I wonder if any of you guys out there would like to hire the guy that drew that Fig 8 picture. How'd you like to have a few dozen panel schedules drawn up like that?.

    Fred Madden
    Reply to this comment

  • There was an outfit in Missouri called Electenergy Technologies that was also selling this snake oil. They claimed to reduce I2R losses in power lines and save 10% of a customer's electric use by adding power factor correction capacitors! The savings in all installations was always 10%, regardless of the customer, regardless of whether they paid power factor charges, regardless of use or length of incoming power drops. Fishy. eh?

    There is a tiny, but real reduction in I2R losses in incoming power lines, even without power factor metering, that can occur as a result of adding capacitors. As has already been pointed out, it is ludicrous to expect these gizmos to actually save a significant amount of energy. These companies should all be brought up on fraud charges if they actually sell these things to consumers.

    Lawrence Lile, P.E.
    Reply to this comment

  • > Hello Heinz: > Just a note with more information in my reply to you. I really enjoy this type of discussion so I am not replying to be arrogant or argue but just to enjoy the forum. > I have designed and wired several houses and small businesses and am familiar with the actual physical wiring as opposed to a one line diagram. I have > been doing this type business since 1963 and for much of that time have taught telecom power system design and installation to both technicians and > engineers. I am very familiar with electrical principals and power terms such as VA, WATT, PF, batteries etc. and say this not to brag or blow my horn but > hopefully only to lend some credibility to my comments. Many devices in the home or business often share a common circuit protected by a common wire from one circuit breaker. So the sum of the current in > paralleled circuits for such a common circuit are shared at points along the way from the associated circuit breaker and then through the final input feeders. > If there is in theory a power factor correction device for the inductive and capacitive loads placed on that same circuit there is a reduction in current feeding through that circuit breaker. Example: a 120VAC single pole 20 amp circuit breaker feeding a total of 1500 watt of load at .8 PF consisting of both resistive and inductive loads. The total current through the breaker would be I = 1500/96 = 15.63 or 1876VA. Lets say for the purpose of discussion I correct the power factor to unity with the addition of power factor capacitors > and/or inductors. Many computers because of their switch mode power supplies have capacitive reactance and thus require inductive power factor correction > devices instead of capacitive. The current in the shared common lead for this 20 amp circuit breaker protected circuit will now be 12.5A. All though this > would result in very little savings for I2R losses it does in fact lower the over all consumption of wattage (wattage for the devices served plus I2R) for that location and also the power generating facility including the distribution grid. This would in fact lower the energy cost for all concerned including the final energy user based on the kwhr. All though only a very small > amount it does in fact reduce power usage. The question is does the investment justify the savings. Also a legitimate question would be what does it do in > respect to harmonics and their effects at this and other served locations. Incidentally--------although a properly balanced single phase 120/240 > circuit does not have current flow in the neutral lead there is in fact the flow of current in the neutral lead as result of unbalanced loads on leg 1 and leg > 2. I have measured it many times. Also I am aware that many large businesses are billed for their electrical > energy usage based on VA and not watt. I also know that the power company can penalize for reactive loads poorer than what is usually established at .8 pf. > For interest sake and training objective reinforcement I have often used large AC capacitors as a load on a UPS and have my students measure the UPS load > current and since UPS are rated in VA I have them calculate the VA. I also have them observe with an oscilloscope the shift between current and voltage. > I then have them turn off the AC input to the UPS and observe the percentage of load on the UPS batteries. They are astounded when they see almost no > detectable load on the batteries. Really re enforces the concept of wattless power > Thank you for this opportunity to share information. > Walt > >

    Walt
    Reply to this comment

  • I it seems to good to be true, it probably isn't true. How much do they want for this thing?

    Jack Kagaan
    Reply to this comment

  • Mike, Has anyone in California complained to the California Board for Professional Engineers and Land Surveyors? This reads to me like rendering engineering opinions without the benefit of a professional license. James

    James Mercier, P.E.
    Reply to this comment

  • I think, and correct me if I am wrong, that the basic concept behind the power save is not to correct the power factor in the home, but to phase out the current and Voltage. In theory by phasing them out you can cheat the meter into reading about 30% less, if the theory is correct.

    Michael Gonzalez
    Reply to this comment

  • My calculations show the Santa Clara University article to be correct. Figure 1 in the article does show R1, R2 and R3 and not just R1. The served circuits are in parallel so obviously the 36 watt difference comes from eliminating I2R loses in all circuits including windings, connector devices etc. and not just R1. If those are actual measuments then the math does not lie. P = E X I X PF. As the article clearly points out, the total current is an algebraic aggregate of all currents passing through the wattmeter. Thus the difference in the power shown is because of the corresponding algebraic aggregate of the various power consuming devices including the I2R loses. I believe the reduction in power using the power saver over a month of time 24 hours a day could be significant enough to justify installing one. A similar technology was often used back in the early 1980's and was then called a power modulator. It was used on large HVAC units to reduce energy consumption. I remember it well because it created harmonics that caused problems with SCR rectifiers. It was necessary that the Bell Labs design and sell to the user a filter for the harmonics created. So the device will indeed save on the power bill---the question is how much and what are the effects concerning harmonics. The article briefly alluded to this at the very end.

    Walt
    Reply to this comment

  • This is very interesting and it shows how pervasive these hoaxes can be. I ran into this a year ago after reading an article in the Louisville Courior Journal newspaper about an Indiana firm, Titon Energy, that promates these devices, which were touted to be patented by the firm's President. They have a website that showed a demonstration of their "Utilisaver" device reducing the amperage to a pool pump motor claiming it would reduce utility bills.

    They used a "Kill-A-Watt" meter, a handy $27 plug in device that measures voltage, amps, watts, volt-amps, power factor, and, over time KWH's.

    I bought one and went to the same place they filmed their demo, a pool supply store, and ran the same test.

    Without the "Utilisaver" connected the 120 volt motor drew 9 amps at 69% power factor, 740watts, and 1066 voltamps. With the "Utilisaver" connected the supply side reading [the one the utilty company meter sees] was 6.4 amp at 98% power factor, 740watts, and 757voltamps. The same wattage, the same effect on the utility meter; NO SAVINGS.

    I could never get the Titon Energy people to clarify this. They kept claiming that the utility meter reading is based on amperage and the reduced amperage means lower billing.

    I don't know how these companies continue to operate under the radar of law enforcement.

    James Wilson, PE
    Reply to this comment

  • Hello, since 1 watt= 1 volt x 1 amp isn't it the same thing. 1 KW hour = 1 KVA hour ? The way I understand it, it does not matter what you call it they are both the same. If my understanding is incorrect please let me know.

    Mark Higgins
    Reply to this comment

  • Thank You Mr. Rosen

    Ron Carter
    Reply to this comment

  • What about X power

    http://www.ilovetechno.myfti.biz/FTI2006/xpower.asp

    If there was a way for you to reduce your power bill up to 25% EVERY month, would you want to know about it? All electricity is subject to surges from time to time, which result in spikes or parasitic peaks that can be damaging to your household equipment and appliances. These spikes simply consume electricity, resulting in overheating, which can shorten the life of your appliances and wiring. In extreme cases electrical spikes can cause burns, blow outs and power cuts. Now, thanks to the XPower Energy Saver, there is a smart way to reduce up to 25% of your electricity consumption each and every month.

    HERE'S HOW IT WORKS

    XPower Energy Saver improves the power factor by reducing the amount of electricity that is used from the utility company. This is accomplished by supplying electricity locally at the load by the use of specially designed capacitors. These advanced capacitors store the additional electricity needed for stabilizing electric current within an inductive load.

    Therefore, the amount of electricity purchased from the utility company by a power factor optimization has been greatly reduced, resulting in power savings for the home or office.

    Xpower Energy Saver Item #1200R.........US$249.95

    Xpower Tools

    • View Your State's Electricity Rate (ext. link) • View Independent Test Results (.pdf file) • Test Report (.pdf file) • Xpower Demo Video (.wmv file) • Xpower Savings (.pdf file) • Xpower product manual

    Frank David
    Reply to this comment

  • These devices have been marketed for years to many who are not tech savy enough to understand that in a residential application, there is little to no benefit from this device.

    I've seen displays in major home improvement centers which show a motor with no load and an amp meter before and after the device is enabled. Of course correcting PF will result in amp reduction, which looks impressive on a customer display. However, most non-electrial engineers don't understand the fact that the device is only reducing amps and not watts. Utility meters measure watts only, and not reactive VARs. The average person doesn't understand the concept of power factor. All they see is reduced amps by looking at the meters and think that this translates into energy savings (KWH's). But unfortunately, they are mislead.

    These devices have been marketed under many different names over the years - including "The Green Plug", "Power Commander", etc.. In many cases, the literature touts a "fact" that the technology was invented by NASA, and is also known as a Nola device.

    P.T. Barnum had a favorite slogan about those who fall for this kind of stuff...!

    Spencer Morasch
    Reply to this comment

  • All this thing is, it seems to me, is a big capacitor. It actually just throws off the power factor big time, but the residential meter can't tell (as the utility just assumes residents have near perfect power factors). It shifts the load of the home, consuming more reactive power (Q), and the meter only counts the real (R) power, making energy consumption seem to "dissapear". We actually talked about this in my Circuits II class. If a VA meter (a meter that measures complex power) were connected to the home, there would probably be a pretty hefty charge for a non-corrected power factor. The report is junk, but I think this product would actually work by cheating the power company's residential meter by creating a bad load power factor (in my book, stealing).

    David Williams
    Reply to this comment

  • wow! what if I connect one of these with an ESE lightning rod and those grounded matress? Does PhD now stands for "Physics Dysfunction"?

    Carlos Leite
    Reply to this comment

  • Very good response. A friend of mine once told me that you could sell people rocks as long as you could convince them they would be richer after they bought it.

    An alternate explanation, meant in humor, is that this is a secret plot by the power companies to better their distribution effeciency while making the consumer flip the bill. ( this will only work if about 50 or 60 Million of us install these contraptions! )

    I will be very interested to see the mfr's response. My money is on silence as a response however.

    Best Regards:

    Scott Stocking Product Manager - Variable Frequency Drives & Motor Control Centers French Gerleman Electric St. Louis, MO.

    Scott Stocking
    Reply to this comment

  • I sure would be interested to hear if there was a reply from Power-Saver regarding the letter dated March 12, 2007.

    Joseph Burkland
    Reply to this comment

  • In a nut shell, what do I tell my customers In laymen terms. what advantage will they get, if any People have been asking me. and I don't have any answers. Thank you for this information

    Frank's Electric
    Reply to this comment

  • Power factor correction capacitors are not new. When used to correct for bad power factor at industrial plants they can pay for themselves. This is the case only where the utility has penalties for bad power factor or charges for KVAR's. However these systems have to be engineered as the harmonics that they can generate can be extremely harmful to the distribution system. I have been involved in a couple of installations where pf correction caps were used. In both cases the caps were improperly applied resulting in problems so serious with VFD's, soft starts, and various other sensitive electronic equipment (including PC's) that we were forced to disconnect the caps. Any application for power factor correction must be designed by a competant engineer or you are asking for trouble.

    After reading some of the excerpts from the reports either the two so called PhD's are entirely clueless or the report is a fraud which I believe to be the case. I checked with the Santa Clara University's Electrical Engineering Department- as I suspected they do not have any Professor's named Mutlu or Rahman. I would say a class action lawsuit would be in order here.

    Bill Poindexter
    Reply to this comment

  • As your other readers have commented, this scam reappears periodically in different forms. I remember the "Phase Liner" product that was being marketed many years ago. It was a black box that connected to the service entrance. The contents of the black box were secret, but it was almost certainly a capacitor to improve power factor. The sales pitch was clever. They had an ammeter and a small unloaded induction motor (low power factor) mounted on a piece of plywood. They would turn on the motor without the black box, and the current would be nearly full scale. Then they turned on the black box and the current dropped. This company also had endorsement by a PhD at a university in Texas. He didn't seem to be aware that utility meters read only kilowatt-hours. The PhD was probably another victim of the scam! --Jim

    Jim Cook
    Reply to this comment

  • I have succeeded in manufacturing a residential power factor correction system by utilizing a Dog, a Pony, a small amount of Smoke and a Mirror! This device is not sold in stores!

    Mark Prairie
    Reply to this comment

  • I remember when I first learn this topic in college. I thought about running home and installing PF correction caps on all my inductive appliances. That was nearly 10 years ago, and of course I can't remember all the details, but I do remember that I had to install the caps directly across the motor leads, not at the service entrance for them to do any good. My intention at that time was not to save money (I had good professor who explained the KWH meter on my house), but to reduce the reactive (or wasted) energy being used in my home. It seemed to be the "green" thing to do. I envisioned the energy savings to be had if everyone did the same (idealistic, dreaming college student that I once was). So, will somebody please bring me back to reality and explain the issues surrounding why appliance manufacturers don't produce PF corrected products in the first place?

    Mark Goth
    Reply to this comment

  • I agree with the author and there is more of this trash on the market.

    See clames by "e-con line conditioners" and calculations by "power survey"

    Tim Banks
    Reply to this comment

  • I heard of this way back in 1980 when I attended Navy electricians mate "A" school in Great Lakes. I'm glad I didn't pay an electric bill back then otherwise I may have ran home to build one of these contraptions only to have wasted a portion of my life on a futile endeavor!

    Craig Monin
    Reply to this comment

  • If you visit the companies website now you will find the "university" document has been rahter ham-handedly hacked to call out Power-Save 1200 in place of ABET 2201. At least we know the company president is addressing some of the questions in the letter ;<)

    Ken Lillemo
    Reply to this comment

  • Aside from the claims made by power-save, perhaps the "Chevron Car Wash" and "Typical Family Residence" video on the power-save web site would be better suited to demonstrate that avoiding this close proximity to live uninsulated components without proper PPE is restricted by OSHA and NFPA 70E. Personally, I was amazed that this organization openly airs a video full of violations without taking proper precautions against approach distances, flash and shock protection without wearing mandated PPE for such task. Let's not overlook the clear example of what not to wear and strictly advocate that PPE is required in these instances to guard against injury.

    MJ
    Reply to this comment

  • From their web site. This thing is magic Reduces Electrical Bills up to 25% or More Every Month! ---> Pays for Itself in Less Than One Year! ---> 60-Day Money Back Guarantee! ---> Installs in Less Than 30 Minutes! ---> Increases Motor and Appliance Life! ---> UL Tested and Listed! ---> Over 10,000 Customers are Saving Money Right Now! ---> Eliminates Power Surges! ---> Reduces 'Noise' in the Electrical System!

    Fred Madden
    Reply to this comment

  • I looking forward to the reply from the company.

    Pat
    Reply to this comment

  • I hope these guys get slapped. What a bunch of crap. If they actually have PhD's, the the school that supplied them with those titles should be slapped too.

    Jason Allington
    Reply to this comment

  • Recently we were given a presentation on a device named "Electroflow." The claims made for it are: Voltage Improvement, 3-Phase Balancing, Surge Protection, Harmonics Reduction, Power Factor Correction, Capacity Release, Brownout Protection, Voltage Failure Protection, Harmonics Filtering, and Phase Loss Synthesis. Whew, all in one unit. Have you had any experience with this unit? Thanks

    John Voitl
    Reply to this comment

  • Thank you all for your resounding confirmation of what seemed to be the case. Several of you asked if I ever got a reply to my letter. Well, one day I received a phone call from someone who seemed to be a salesman for the company who said that if enough units were involved "he could cut me a deal." When I pointed out that there were several rather serious technical questions that had been addressed to the president and that needed to be answered before we went any further he lost interest. That was the last I heard of it. Thanks again. Heinz R.

    Heinz R.
    Reply to this comment

  • I just love it when some businessman discovers the "magic" of capacitors and creates a phantasy land of blather, graphs, assertions, etc. to show how much you will save. These pop up every few years and are all the same foolishness. Let's not even get into a single formula, electric law, diagram, or anything and just remember one simple fact: Whatever you do to any system, the system losses are facts of the universe as we find it and you cannot save more than you are losing. If you think you can, then you must believe in perpetual motion and entropy decreases.

    kevin cassidy
    Reply to this comment

  • Bravo: to Mr Heinz Rosen!

    A credible and interesting study to Power-Save. Looking forward to the response. though doubtful they will reply.

    Les Weatherford
    Reply to this comment

  • The fact that residential meters measure power consumption in kw hours makes the use of power factor correction a moot point. Why go any further or say any more? But we know if we where copper bracelets during a full moon we can cure the gout.

    Tom Kelly
    Reply to this comment

  • Nothing new here. It is kind of fun to be in this business and see this stuff regenerate itself over the years, like a Phoenix out of the ashes. Trouble is, they will probably make more money than most of us:

    Danny Langston
    Reply to this comment

  • SNAKE OIL........PURE AND SIMPLE.....

    IF ANYONE WANT TO GO FOR THIS THEY ALSO SHOULD BUY ONE OF THE SURGE PROTECTORS THAT WILL REDUCE THEIR ELECTRICAL BILL... AFTER ALL A SECOND DOES OF SNAKE OIL MAY BE GOOD FOR YOU!

    John West, Sr.
    Reply to this comment

  • We had a good laugh over these scam-gadgets at a recent IEEE lunch. Then came the debate over where the VARs go on the grid, and most had the wrong answer.

    Matt
    Reply to this comment

  • Judging by the address of the Company, I suspect that the President and CEO of Power-Save is a Cal Poly University student who, after an introductory class on power systems, claims to have the cure for residential power factor. :-)

    Jim
    Reply to this comment

  • These gimmicks seem to pop up from time to time. I've seen several like this in the last 20 years, all phoney.

    Bob
    Reply to this comment

  • Just another scam to make someone rich. I have some magnetic water conditioners and magnetic gas saving units for anyone interested!

    beanland
    Reply to this comment

  • These things were about due to pop up again I reckon. Hadn't seen them for awhile. The last ones I saw had some MOVs and other gingerbread in there. They didn't work either. Tell your customers to follow the kids around and turn lights off. That really will save on your electric bill.

    Fred Madden
    Reply to this comment

  • I had the opportunity in my college days to to visit a small company with an investment group that was claiming their "magic black box" was able to generate more power than it used when placed infront of a motor. If I remember correctly the premise was the same as this unit. However the actual "inventor" was in Africa and couldnt leave the country because of a Visa problem. I haven't seen the motor device come to market yet. Maybe this is its offspring?

    John S
    Reply to this comment

  • This is the nth time I am coming across this kind of money making scams. I am sure the POWER -SAVE company would have already sold the idea to some thick head top executives in some companies and made their buck.

    PRASADA
    Reply to this comment


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