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**What is the Power Factor?**

**Power factor is the ratio of active power, measured in kilowatts, to apparent power, measured in kilo-volt amperes (or in kVA), power factor is the measure of effective use of electrical energy. **

Below, is the power factor triangle, which shows the relation between power factor, active and reactive power.

Apparent power is the measure of the total amount of power that is used to run electrical equipment, active and reactive.

The power factor is how effectively you are using electrical energy. It is expressed as a number less than or equal to 1.

The lower the **power factor,** the less efficient electrical power usage. For well-designed electrical motors the PF = 0.95 while for single-phase bad motors pf = 0.75

## Power factor formula

Read Also my other article

Power factor correction, 8 important answers.

**What is Power Factor Correction?**

## Should I Improve the Power Factor at My Home?

**benefits of power factor correction**

## What causes a low power factor?

## Low power factor disadvantages

**Lower power usage efficiency,**A low power factor means you are wasting a lot of power. A power factor of 0.7 means only 70% of the total supplied power is used by your business or the industry and 30% is wasted in the circuits and networks. The wasted power is the reactive power.**Higher cost,**Most industrial loads are inductive, which means that the power factor is less than unity. The lower the power factor the greater amount of power is drawn. Which indicates that the greater current is drawn for the loads.

**PF = cos Φ = (P / VI) **

**I = P / (V cos Φ)**

The increased current requires a larger generator size, larger transformer, and larger cable sizing.

The increased amount of current also increases the amount of heat produced due to power losses, i.e. the lifetime of the equipment is also reduced.

All these things increase the large amount of cost of installation and also limit the expansion of plant or industry.

## How to improve the Power factor?

## Power factor improvement formula and example

How to calculate a capacitor bank to improve the power factor? is an important question, **Use our online PF correction capacitor calculator below.**

But, as a quick Tip, the PF correction capacitor formula is **C = 1/(2πf ( V ^{2}/Q)) **

Where,

V is voltage

Q is reactive power

**Q = √(S ^{2} – P^{2}), **

**P** is active power and **S** is apparent power

**Power factor improvement example**

Assume we have a three-phase induction motor. Its power = 10 kw, PF = 0.78, working on a 400V 50 HZ, the source we need to add a capacitor in parallel with the motor to improve its power factor.

**PF = P / S**

S = P/PF = 10000 / 0.78 = 12.8 KVA

While P is the active power of the load in Watt.

S is the apparent power in VA.

**The reactive power Q** **formula is:**

Q = √(S^{2} – P^{2}) = 7.98 KVAR

Q =V^{2} / X ⇒ X = V^{2}/Q

**X = V ^{2}/Q = 1/2πfC**

**C = 1/(2πf ( V ^{2}/Q)) = 15.8 µf**

**This means this motor needs a 15.8 µf power factor correction capacitor to be connected in parallel.**

Use the below power factor improvement calculator.

## What is the unity power factor?

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