The Facts behind the so-called ENERGY SAVERS

Question:  Is it true that you will save on your electricity bill if you buy and use the so called “Energy Saving Device” sold in most popular malls today?

Answer: No

Question: But how come that in their demonstration, the current decreases when the device is plugged in? I’ve seen it with my own eyes.

Answer:  Note that only the current was shown in their demo but not the killowatthour reading. Electric bills are computed based on Kilowatthour readings and not the current reading alone.

Question: But doesn’t it follow that when the current is reduced, the kilowatthour (electricity bill) also goes down?

Answer: Not in this case. There are 2 different types of currents that exist in the setup they use; The “RESISTIVE” (in-phase) current and “REACTIVE” (out of phase) current. A fluorescent lamp with ballast and any appliance with motor produce both RESISTIVE and REACTIVE currents which are both displayed by the current meter. But among the two currents, only the RESISTIVE current can be sensed by the Kilowatthour meter and contributes to its actual reading as shown in our electricity bill.

This is the reason why they only use fluorescent lamp with ballast or an appliance with motor in their demo. Using other devices such as an incandescent lamp, TV, or computer which only produce RESISTIVE current will not have the same result.

Question: I still don’t get it. Can you use an example?

Answer: Imagine a glass of newly poured beer almost filled to the brim. The beer occupies 2/3 of the container while the remaining 1/3 are just bubbles.

REAL power is represented by the beer, while APPARENT power represents the bubbles.
This is what happens when you use fluorescent lamp or any appliance with a motor and you plug in the energy saving device. In the analogy,  the fluorescent lamp or motor produces both the beer and the bubbles, while the so called “Power Saver” device removes those bubbles but has no effect on the actual amount of beer which represents the Kilowatthour readings wherein our electricity bill is based.

Question: Then what is the device good for?

Answer : It’s a power factor correction device (simply capacitor). It doesn’t affect the Kilowatthour reading in anyway. You will still pay the same amount of energy you use even with such device. In fact, it can even add a small amount to your bill due to the additional components like LED lamps that goes with it. However, large commercial and Industrial consumers may have different considerations.

About the author:

Having worked in Meralco electrical laboratory and after conducting elaborate testing methods on numerous commercial Energy saving devices, we’ve seen that most of these products claiming to save on electricity bills are either;

1. Power factor correction devices which are merely capacitors.
2. Harmful power reducing devices that clips and distorts the actual power supplied to the load resulting to the appliance reduced power output other than what it was originally designed to deliver. This therefore extend the time it needs to work to produce the same output. This doesn’t help as electricity bills are based on energy (Kilowatts multiplied by time).

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