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Household Power Saver
Household Power Saver - Efficent? What is the real truth?

A household power low voltage saving devices has recently received a lot of attention from both consumers and manufacturers. It is generally used in residential homes to save energy and to reduce electricity bills. It is a small device which is to be plugged in any of the AC sockets in the house (Mostly near Energy Meter). Moreover, some of the companies claim that their power savers save up to 40% of the energy.

Many people believe that the claims made by the power savers manufacturing companies are false. Almost all people who buy power savers do it to reduce their electricity bills.

Many people who have used these power savers said that they could reduce their electricity bills with the devices; however the reduction was not as much as they had expected. Moreover, they could not figure out if the reduction in electricity bills was due to the power savers or because of their efforts to reduce their electrical usage. There have been several serious discussions about the genuineness of the device.

In this note, we will try to find the real truth behind these power savers which claim to save as much as 40% of energy.

Working Principle of Power Saver as per Manufacture

A Power Saver is a device which plugs in to power socket. Apparently just by keeping the device connected it will immediately reduce your power consumption. Typical claims are savings between 25% and 40%.

It is known that the electricity that comes to our homes is not stable in nature. There are many fluctuations, raise and falls, and surges/Spikes in this current. This unstable current cannot be used by any of the household appliances. Moreover, the fluctuating current wastes the electric current from the circuit by converting electrical energy into heat energy.

This heat energy not only gets wasted to the atmosphere, but also harms the appliances and wiring circuit.

Household power saver device - Schematic diagram
Household power saver device - Schematic diagram

Power Saver stores the electricity inside of it using a system of capacitors and they release it in a smoother way to normal without the spikes. The systems also automatically remove carbon from the circuit which also encourages a smoother electrical flow. This means that we will have less power spikes. More of the electricity flowing around circuit can be used to power appliances than before.


Basically it is claimed that Power savers work on the principle of surge protection technology. Power savers work on straightening this unstable electric current to provide a smooth and constant output. The fluctuation in voltage is unpredictable and cannot be controlled. However, the power savers utilize current fluctuation to provide a usable power by acting like a filter and allowing only smooth current to pass through the circuit. Power savers use capacitors for this purpose. When there is a surge of current in the circuit, the capacitor of the power saver stores the excess current and releases it when there is a sudden drop. Thus only smooth output current comes out of the device.

Moreover, a power saver also removes any type of carbon in the system, which facilitates further smoother flow. The main advantage of power savers is not that they provide a backup system in times of low current, but that it protects the household appliances. It is known that a sudden rise in the power can destroy the electrical appliance. Thus, the power saver not only protects the appliance but also increases its life. Moreover, they also reduce the energy consumption and thus the electricity bills.

The amount of power saved by a power saver depends on the number of appliances on the electrical circuit. Also, the system takes at least a week to adapt itself fully to the circuit, before it starts showing its peak performance. The maximum amount of voltage savings will be seen in areas where in the current fluctuation is the highest.

Household Power Saver Scam Review

Power Factor Correction for residential customers (home owners) is a scam? At most, each unit is worth as an investment. Power factor correction does make sense for some commercial / industrial customers.

Many companies are promoting and advertise that their Power Saver unit are able to save domestic residential power consumption by employing an “active power factor correction” method on the supply line. The concept seems pretty impressive as the concept is true and legally accepted. But practically, we will find that it’s not feasible.

To support above statement first we need to understand three terms:

  1. Type of electrical load of house,
  2. Basic power terminology (KW, KVA, KVAR).
  3. Electrical tariff method of electricity company for household consumer and industrial consumer.

There are basically two kinds of load that exists in every house: one that is resistive like incandescent lamps, heaters etc. and the other that’s capacitive or inductive like ACs, refrigerators, computers, etc.

The power factor of a Resistive Load like toaster or ordinary incandescent light bulb is 1 (one). Devices with coils or capacitors (like pumps, fans and florescent light bulb ballasts)-Reactive Load have power factors less than one. When the power factor is less than 1, the current and voltage are out of phase. This is due to energy being stored and released into inductors (motor coil) or capacitors on every AC cycle (usually 50 or 60 times per second).

There are three terms need to be understand when dealing with alternating (AC) power.

  1. First Term is kilowatt (kW) and it represents Real power. Real power can perform work. Utility meters on the side of House measure this quantity (Real Power) and Power Company charge for it.
  2. The second term is reactive power, measured in KVAR. Unlike kW, it cannot perform work. Residential customers do not pay for KVAR, and utility meters on houses do not record it too.
  3. The third term is apparent power, referred to as KVA. By use of multi meters we can measure current and voltage and then multiply the readings together we get apparent power in VA.
Power triangle
Power triangle

Power Factor = Real Power (Watts) / Apparent Power (VA)

Therefore, Real Power (Watts) = Apparent Power × PF = Voltage × Ampere × PF.

Ideally a PF = 1, or unity, for an appliance defines a clean and a desired power consumption mostly Household Equipments (The dissipated output power becomes equal to the applied input power).

In the above formula we can see that if PF is less than 1, the amperes (current consumption) of the appliances increase, and vice verse.

With AC Resistive Load, the voltage is always in phase with the current and constitutes an ideal power factor equal to 1. However, with inductive or capacitive loads, the current waveform lags behind the voltage waveform and is not in tandem. This happens due to the inherent properties of these devices to store and release energy with the changing AC waveform, and this causes an overall distorted wave form, lowering the net PF of the appliance.

Manufacture claim that the above problem may be solved by installing a well-calculated inductor/capacitor network and switching it automatically and appropriately to correct these fluctuations. A power saver unit is designed exactly for this purpose. This correction is able to bring the level of PF very close to unity, thus improving the apparent power to a great extent. An improved apparent power would mean less CURRENT consumption by all the domestic appliances.

So far everything looks fine, but what’s the use of the above correction?

The Utility Bill Which We pay is never based on Apparent Power (KVA) but it is based on Real Power (KW). The utility bill that we pay is never for the Apparent Power- it’s for the Real Power.

By Reducing Current Consumption Does Not Reduce Power Bills of Household Consumer.


Study of Power Saver in Domestic Load

Let us try to study Household’s Reactive-Resistive Electrical Load and Voltage Spike Characteristic by example.

1. Power Saver in Reactive Load of Home

Let’s take One Example for reactive Load: A refrigerator having a rated Real Power of 100 watts at 220 V AC has a PF = 0.6. So Power=Volt X Ampere X P.F becomes 100 = 220 × A × 0.6 Therefore, A = 0.75 Ampere

Now suppose after Installing Power Saver if the PF is brought to about 0.9, the above result will now show as: 100 = 220 × A × 0.9 And A = 0.5 Ampere

In the second expression we clearly show that a reduction in current consumption by the refrigerator, but interestingly in both the above cases, the Real Power remains the same, i.e. the refrigerator continues to consume 100 watts, and therefore the utility bill remains the same. This simply proves that although the PF correction done by an energy saver may decrease the Amperage of the appliances, it can never bring down their power consumption and the electric Bill amount.

Reactive power is not a problem for a Reactive Load of Home appliances like A.C, Freeze, motor for its operation. It is a problem for the electric utility company when they charge for KW only. If two customers both use the same amount of real energy but one has a power factor of 0.5, then that customer also draws double the current. This increased current requires the Power Company to use larger transformers, wiring and related equipment.

To recover these costs Power Company charged a Penalty to industrial customers for their Low power factors and give them benefits if they improve their Power Factor in. Residential customers (homes) are never charged extra for their reactive Power.

2. Power Saver in Resistive Load of Home

Since a resistive load does not carry a PF so there is not any issue regarding filtering of Voltage and Current, So Power = Voltage X Current.


3. In Voltage Spike / Fluctuation condition of Household Appliances

In above discussion simply proves that as long as the voltage and the current are constant, the consumed power will also be constant. However, if there’s any rise in the input voltage because of a fluctuation, then as explained above your appliances will be forced to consume a proportionate amount of power. This becomes more apparent because current, being a function of voltage, also rises proportionately. However, this rise in the power consumption will be negligibly small; the following simple math will prove this.

Consider a bulb consuming 100 watts of power at 220 volts. This simply means at 240 volts it will use up about 109 watts of power. The rise is just of around 9% and since such fluctuations are pretty seldom, this value may be furthermore reduced to less than 1%, and that is negligible.

Thus the above discussions convincingly prove that energy savers can never work and the concept is not practically feasible.


What happens when Power Saver is installed?

The Fig shows the result of using Power Saver. The air conditioner (which has a large compressor motor) is still consuming reactive power but it is being supplied by a nearby capacitor (which is what is in those “KVAR” boxes). If you were to mount it at the air conditioner and switch it on with the air conditioner plus you sized the capacitor perfectly, then there would be no reactive power on the line going back to the fuse panel.

If the wire between your fuse panels is very long and undersized, reducing the current would result in it running cooler and having a higher voltage at the air conditioner. These savings due to cooler wiring is minimal.

What happens when Power Saver is installed
What happens when Power Saver is installed

A further complication is that if you install the “KVAR” unit at the fuse panel, it does nothing for the heat losses except for the two feet of huge wire between the fuse panel and the utility meter. Many KVAR units are marketed as boxes that you install at a single location.

If your power factor box is too large, then it will be providing reactive power for something else, perhaps your neighbor.

Conclusion

Power factor correction devices improve power quality but do not generally improve energy efficiency (meaning they would not reduce your energy bill). There are several reasons why their energy efficiency claims could be exaggerated.

First, residential customers are not charged for KVA – hour usage, but by kilowatt-hour usage. This means that any savings in energy demand will not directly result in lowering a residential user’s utility bill.

Second, the only potential for real power savings would occur if the product were only put near in the circuit while a reactive load (such as a motor) were running, and taken out of the circuit when the motor is not running. This is impractical, given that there are several motors in a typical home that can come on at any time (refrigerator, air conditioner, HVAC blower, vacuum cleaner, etc.), but the Power Saver itself is intended for permanent, unattended connection near the house breaker panel.

And certainly not in the way the manufacturers recommend that they be installed, that is, permanently connecting them at the main panel. Doing that drags the power factor capacitive when the inductive motors are off and could create some real problems with ringing voltages.

The KVAR needs to be sized perfectly to balance the inductive loads. Since our motors cycle on and off and we don’t use the air conditioner in the winter, there is no way to get it sized properly unless we have something to monitor the line and switch it on and off capacity (capacitors) as necessary.

Adding a capacitor can increase the line voltage to dangerous levels because it interacts with the incoming power transmission lines. Adding a capacitor to a line that has harmonic frequencies (created by some electronic equipment) on it can result in unwanted resonance and high currents.

For commercial facilities, power factor correction will rarely be cost-effective based on energy savings alone. The bulk of cost savings power factor correction can offer is in the form of avoided utility charges for low power factor.

Energy savings are usually below 1% and always below 3% of load, the higher percentage occurring where motors are a large fraction of the overall load of a facility. Energy savings alone do not make an installation cost effective.

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Jignesh Parmar

Jignesh Parmar has completed M.Tech (Power System Control), B.E (Electrical). He is member of Institution of Engineers (MIE), India. He has more than 13 years experience in transmission & distribution-energy theft detection and maintenance electrical projects.

193 Comments


  1. jack grossell
    Feb 18, 2021

    I plugged in a 250wat light inline with a KWH meter’ and got a reading, then I did the same with a “electricity saving box” plugged in line with the light, if the “electricity saving box” works I should have gotten a different reading, but I did not proving those things do not work as they clam. Em I right on testing that device that way?? Thank you for your time. jack


  2. Susanna Dzejachok
    Feb 07, 2021

    Thank you for the interesting and helpful article.


  3. GERALD RHODES
    Feb 05, 2021

    IF IT SOUNDS TO GOOD TO BE TRUE IT IS.

    CAPACITORS STORE ENERGY THEN RELEASE IT.


  4. John Foley
    Feb 03, 2021

    Hi, just wondering if Two different power energy power saving devices were were used instead of one what would happen…..?!!!


    • Gordy
      Feb 10, 2021

      The light on Rudolphs nose would FINALLY work. Christmas is saved.


  5. king
    Feb 02, 2021

    “Cleans carbon’. All you need to know. Much like headlight fluid replacement. These are guys who sell beach front property in Idaho. They are not concerned about lawsuits…around only for “a limited time”. By the time the scams are reported, they are sipping Mai Tais on that Idaho beach.


  6. Philip
    Feb 02, 2021

    When there is no customer service or support email for device, don’t waste your time on it.
    Here are my “common sense” questions to ask about power savers.
    I would not spend even a wooden nickel on these devices!:
    Hi whoever you may be,
    Your product is certainly every enticing. However, I have yet to find any information on the Web that gives me reason to invest.
    First, I do not understand how your product is related to Ohm’s Law.
    Second, as far as I know, my energy costs are based upon a measuring device outside my home to calculate how much electricity/energy I am using. How does your device (or devices) interact with this Electrical Meter? It would seem logical to have some kind of surge protector/regulator outside the house, before the electricity enters the counter. How does your device affect the quantity coming into the house? Or does your device affect the electrical demands of the devices in their start-stop cycles? (I do recall that many years ago there was a big rush to leave all lights on in skyscrapers because turning the lights on took a greater surge and thus it was less expensive to leave them on.)
    Third, you say “there are no electricity saving benefits for heating appliances, such as electric stoves, electronic cookers, etc.” So wh;y bother with your device? Please elaborate on the “etc.
    I have 3 wine coolers, 3 refrigerator/freezers, 1 freezer, 1 built-in stove-top, 1 microwave oven, and 1 convection oven; plus several induction burners. Most are commercial.
    Fourth, I do not understand the reasoning for the geometrical layout for the placement of your devices: on or near the main breaker box, and the rest at 500 sq. ft intervals. How is this to be measured if your rooms are larger or smaller than 500 sq. ft? And why square feet? Doesn’t make sense.
    This is really a great scam and too well presented in the manner of “Trump”


    • Gordy
      Feb 10, 2021

      The relation to electrical principles are these:

      The more ‘ohms’ they sell these scam-claimed devices, the more current(cy) their bank accounts get.
      The resistance is futile.


    • Pam Fleuret
      Mar 05, 2021

      Boy the manner of “Trump” came out of left field and didn’t address the whole of your article. Nullified everything else you said even if you made since.


      • Jimmie chapman
        Mar 06, 2021

        Do you already see what’s going on??. You say F*** trump. By the time Biden gets through with you, you will wish to hell, that you had trump back. And you can bank on it. Be careful for what you wish for. Your getting exactly what you voted for. A nightmare.


    • Jest Sayin'
      Mar 15, 2021

      Trump is selling electrical savings? Hm. I thought I clicked on EEP, not CNN.
      Take your TDS somewhere else.


  7. DEnnis Yoj
    Jan 31, 2021

    All lines / circuits ARE connected together as they all connect ultimately to the two/three supply lines.
    Any capacitor is then connected to all the house circuit’s. Electrician.


  8. g riutzel
    Jan 31, 2021

    Excellent article Technical but well written for laymen and serious homeowners who want to understand how things work.


  9. Shobana prasad
    Jan 16, 2021

    My mom in law bought power saver from Amazon. And plugged it in to save money on electric bill. Hubby tells me that it’s fake. Daughter tells me that we should return it.
    There are 2 plugged in and 3 sitting on a table. I don’t know if it works ❓


    • Dennis Carman
      Jan 23, 2021

      These power savers are 100% fake. The day I got mine , the thing screamed fraud. So since I bought three, I decided I would open one up and take a look inside. There are two lights and two Ted wires going into a black box filled with clay. I cut the black box apart and discovered what I thought might be resin was instead just clay. I cut it apart. Guess what? There is no capacitor, there is nothing! The wires are just stuck in the clay connected to nothing. This is one hell of a fraud.


    • Jason robards
      Mar 02, 2021

      My electric bill has gone down. And that’s using electric heat day and night. Appliances. Electric blanket.. so is this my imagination?


  10. Thomas F Nagle
    Jan 11, 2021

    This reminds me of the old hot-rod magazines (1950’s) that advertised a device that allowed a reservoir of tap water into your car’s carb to increase gas mileage by 10 fold!


  11. dave ascher
    Jan 09, 2021

    despite all the discussion about KV and KVA and cleaning up voltage and current, nobody has addressed several basic questions:

    1- How does plugging one of these “devices” into an outless anywhere in the house affect anything at all plugged into different circuits and different outlets. The “explanations” in the artile and in the desperately positive comments seem to be base on the idea that there is just one line connecting all the devices in the house in serial. In fact, the devices are all connected in parallel and while there may be interactions between the amount of current flowing through different devices connected in parallel, plugging a box with a few capacitors into on outlet does not immediately come to mind as a way to dynamically influence anything going on with all the devices drawing power from all the other outlets – whether on the same circuit of different circuits.

    2- The article says it takes a time (a few days, weeks, or months) for this device to “figure out’ how to reduce your measured (actual Kv) power consumption. I am not an electrical engineer, although I have had some education in electrical and electronic theory, the former involving moters and generators – and the effects of inductive loads on power meters. I cannot imagine what a box containing a few big capacitors, plugged into one outlet on one circuit on the house side of the meter, might be doing to incrementally improve efficiency after it is plugged into the wall. There doesn”t appear to be any “learning” component involved that would examine the wave forms for the voltage and/or current in order to tweak some algorithm (there is NO algorithm to be tweaked) and continuously improve the “cleanliness” of the voltage and current sine waves. Even if there were such an algorithm, something that monitored the noise on the voltage and current, and an algorithm (there appear to be NONE of these) then see question #1.

    3) How has this device and similar devices continued to be sold despite it obviously being a nonsensical fraud? The Federal Trade Commission should have shut down the sale of this device an others like it long ago – after, evaluating the claims about savings, the gobbledigook theory of operation, and/or even running some simple tests – with the help of the folks who sell these silly things, of course, just to keep it on the up and up.


  12. Bernard Bohanon
    Jan 02, 2021

    I believe certain power savers will work and there are those that are a scam. I don’t think a company would put a product out there and say it works without first having it tested and have used it themselves. This could lead to lawsuits especially if the device causes damage and can be proven. You just have to test it for yourself and if you are not pleased get a refund or it will just be a loss. The product isn’t that expensive and if it works you will profit on down the line get your money back in a few months.


    • ruko
      Feb 07, 2021

      The reason they don’t test these bells and whistle boxes is they don’t work. All the outrages claims are anecdotal.They also lie about power suppliers not liking them boxes when in fact these devices actually help the suppliers by raising their power factor. Read the many articles on the net about this scam and you will see the light. They really do have fancy ads don’t they? It’s just carefully thought out bull s….


      • ruko
        Feb 07, 2021

        “the boxes not them boxes”


        • Kay HIgdon
          Feb 26, 2021

          That;s bold, Teach!


          • Kay HIgdon
            Feb 26, 2021

            Hmmm, That’ bold, Teach!


  13. Kevin Russell
    Dec 30, 2020

    ANY “engineer” that made this statement:

    “Moreover, a power saver also removes any type of carbon in the system, which facilitates further smoother flow.”

    Needs to hand in his degree, and ask for a refund from the “higher education” organization that issued the degree and accept a degree as as snake oil salesmen. Or take up a trade cutting lawns. Such crap that is used to sell a product or concept.


    • DEnnis Yoj
      Jan 31, 2021

      “Removes carbon” Sure it does, and it makes one win the lottery.


  14. Lorne DeWitt
    Dec 30, 2020

    I’m a computer engineer, and this product is BS; Don’t waste your money! First the lines coming out of your breaker box are each on it’s own circuit, so that the refrigerator is on it’s own line, the hot water heater is on one of it’s own, the AC, microwave, and individual rooms etc.

    That means if you plug the Instawatt, or any such similar device into an outlet, the absolute most you could ever hope for is; That it might help that single circuit alone. So if you have 40 breaker switches in your breaker box, and assuming the product actually does function as claimed. You would NEED 40 devices to plugged into an outlet that is tied to each, and every single circuit in your house. It simply cannot affect any other circuit outside the one it’s plugged into!

    If you want to reduce the wear, and tear that spikes, and surges causes on your household electronics, and appliances. I would recommend a better investment. You can attain a home surge suppressor unit at any electrical store, near you, or order one online. Don’t be cheap as the better filtration provided by the unit the better protection you’ll get.

    I called city electrical supply in Brooksville, Fl, near my home, and they offer one for $175.00. I seem to remember paying just $40.00 only 10 years ago, and mine’s still going strong!


    • Rick
      Jan 02, 2021

      My house was built in 2002 and at that time, a home surge suppressor was required in all new construction.


      • Jimmie chapman
        Mar 06, 2021

        False statement: there is no such requirement. Where did you get such information.while you cannot be required to purchase such a device, it is not a bad idea,but you cannot be forced to buy such. What if you cannot afford such a unit, will they turn off your service?? Answer: NO. What planet do you live on. This may be a requirement on Mars…not sure. Will have to check. My home have no such devices neither does any my rental houses. Truth being told electric co not interested if your house burns down…not their problem. Law enforcement doesn’t either .fire dept?! Nope, the president…nope. Dog catcher,, ah this must be the one….nope These are things you have to do on your own…..if you like. You do not buy such a unit before they turn on your service. Never asked about, never looked to see if you have one. Nothing to sign stating such as this. This must be a secret requirement .


  15. Dory Campbell
    Dec 21, 2020

    Had there product improved since this article was written?

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