Is the advertised power saver real or scam? This is a question by many perhaps. When I went to malls I observed groups promoting their products that claiming to be a power saver. They even said that by using their product the monthly energy consumption will be decreased by half and also the monthly bill. Let’s find out what the books and the theories say about this. We are about to uncover this whether a real deal or a totally scam product.
Demo and Convincing Method
An ordinary person without any background in electricity or electronics will immediately buy one because what the advertisers did is very convincing for them. Most of the time the advertisers bring with them few stuffs, digital multi meter, electrical load and a power extension. Initially what they do is plug the electrical load (say an electric fan to be specific) into a live power extension. Right after, they will measure the current using a multi meter and record it. Then, they will plug their power saver product in the vacant slot of the power extension which basically makes a parallel connection to the electric fan. Afterwards, they will measure the current. This time the current is smaller than the one without their product plugged in. As a common person this is fantastic. With that product alone and by simply plug it in the wall outlet will decrease the current consumption and the electric bill as well.
Now, we will consider the persons with basic idea in electricity but not practitioners nor engineers. They are also fascinated and convinced by the demo because there is a factual reading from the multi meter and the meter will not lie unless it is already defective. Because the current decreased, the power will decreased as well since the power is just the product of voltage and current. However, the power is not always just the product of voltage and current. You have to take note.
Key Terms and Equations Needed for the Discussion
I will introduce here the basic equations and some key terms that are needed in the following discussions.
Apparent Power = V x I
Real power = V x I x PF
Where V is the voltage, I is the current and PF is the power factor.
Apparent power is the product of the measured voltage and current. Supposing, the voltage provided by the wall outlet is 120V and the current drawn by the electric fan as measured by a digital current meter is 1A, the apparent power is 120W. On the other hand, the Real power is the actual power consumed by the load or the electric fan on our example. The real power is the product of voltage, current and the power factor. What is power factor? This is the multiplier included to compensate the phase difference of the voltage and the current. For resistive load such as incandescent lamp the power factor is 1. When the load is inductive or capacitive in nature such as electric fan, refrigerator, aircon, iron and the likes, the power factor is less than 1.
How the Advertised Power Saver Works
Power savers are design to improve the power factor. If your load is an electric fan which is inductive in nature the power factor will be less than 1, let us say 0.5 to be specific without power saver. When you use a power saver the power factor will become closer to 1, say 0.9. Now, how this affect the current as what the demo said. To explain this very well, we will consider the following:
- Demo Appliance – Electric Fan
- Power Consumption – 100W
- Line Voltage – 120V
The power consumption of any appliances specified in the manual or on the appliance body itself is the real power. Using the equation for the real power we can solve for the current with and without a power saver.
From the mathematical analysis, the current consumed by the electric fan with a power saver is only around half that without the power saver. Maybe you will now conclude that power saver is really a money saver…But wait, there’s more to tell you, continue on reading below.
How the Electric Company Charge Us with Our Usage
It is very important to consider how the electric companies charge us in our monthly energy consumptions. Electric companies are charging us with our true consumption which is based on the real power consumed by our appliances. Now going back to our electric fan example, the 100W is the real power that is fixed. This is the electric meter of the power company will read. If you use a power saver the current will decrease but the power factor will increase and the same real power the appliance will consume. If you are not going to use a power saver, the current is high but the power factor is lower and then the same real power is consumed by the appliance also. Power saver is absolutely cannot lower down your monthly electric bills as advertised.
Is the Advertised Power Saver Real or Scam?
You know the answer now. So don’t be fooled by this advertisers claiming to decrease your monthly electric bill.
Power saver cannot make your monthly electric bill lower because the electric companies are measuring your real power consumption and not the apparent power. The real power consumed by the appliance is constant with or without the power saver. If the apparent power is being used by the electric companies, using a power saver is a good idea since the current will greatly decrease when a power saver is used because the power factor will improve.
Power saver is indeed helpful in other ways. It will help reduce the power losses in the transmission lines. Without a power saver, the current is high and this will correspond to high power dissipation on the transmission lines and this is a loss of the power electric companies. Electric companies may need to increase their cable size to suit the higher current demand. They might repair transformers and other facilities too often because of a poor power factor.
By using a power saver, you just waste your money if your purpose is to lower down your monthly electric bill. However if your purpose is to help the electric companies to minimize their unexpected losses, good job you did it.
Related post by other author : http://electrical-engineering-portal.com/the-real-truth-behind-household-power-savers