# What is the Difference Between Active and Reactive Power?

The difference between active and reactive power is that active power, measured in kilowatts (kW), performs useful work in electrical systems like lighting or heating. Whereas, reactive power is measured in kilovolt-amperes reactive (kVAR), sustains electromagnetic fields and is important for voltage stability and transmission efficiency. It does not directly contribute to useful work output like active power.

## What is Active Power?

Active power, also called real or true power, is the usable part of electrical energy in an AC circuit (measured in watts). It’s the power that gets consumed by devices like lights or motors. Unlike active power, some electrical energy flows back and forth without doing any work. This is called reactive power. To calculate active power, you multiply the voltage, current, and a factor called power factor (cosine of the phase angle between voltage and current). A perfect power factor of 1 means all energy is consumed (ideal scenario).In simpler terms, active power is the electricity you pay for, while reactive power contributes to inefficiencies.

## What is Reactive Power?

Reactive power (VAR) isn’t directly used by your devices, but it’s like a hidden force in AC circuits. It flows back and forth due to inductors and capacitors, and while not useful itself, it’s needed to maintain voltage and current. The downside? It creates inefficiencies by inflating apparent power, requiring more current flow for the same work.

## What is the Difference Between Active and Reactive Power

Active power represents the actual power consumed by electrical devices to perform useful work such as lighting or heating. Whereas, reactive power doesn’t perform any useful work but supports the transmission of active power by maintaining electromagnetic fields in electrical systems. While active power directly contributes to tasks, reactive power is important for voltage stability and efficient power transmission, ensuring that electrical systems function properly even though it doesn’t directly result in useful work output. Here we have mentioned the additional list of differences between Active and Reactive Power

## Similarities Between Active and Reactive Power

While they have these similarities, it’s important to remember they have different purposes. Active power is what actually gets used, while reactive power flows back and forth without doing work.Here we have listed the similarities between active power and reactive power :

• Both are parts of the total picture: Imagine a circuit as a pipe carrying electric power. Active and reactive power are like different types of water flowing in the pipe. Active power is the water you use to do work, like running a washing machine. Reactive power is like the swirling motion the water makes as it goes through a bend in the pipe, not doing any work itself. Together, they contribute to the total flow of power in the circuit.
• They exist in AC circuits: This is because AC stands for Alternating Current, where electricity constantly changes direction. This back-and-forth movement is key to understanding reactive power.
• Measured in different units: Active power is measured in Watts (W), like the wattage of a light bulb. Reactive power is measured in Volt-Ampere Reactive (VAR). They are both units of electrical power.

## Application of  Active and Reactive Power in Real Life

Imagine electricity as water flowing through a pipe. Active power is the water you use, to power lights, devices, and appliances (watts). Reactive power is like pressure; it doesn’t do work but keeps things flowing (VAR). Too much pressure (reactive power) wastes energy and strains the system. We use capacitors and inductors to balance them, like adjusting a valve for smooth water flow. This saves energy and keeps the electricity grid healthy. Below we have stated some of the important real-life applications of these terms:

• Active Power (Watts)- This is the power used by appliances (lights, motors) for their actual function (lighting, heating, etc.).
• Reactive Power (VAR)- It helps motors and transformers work but isn’t used directly.
• Apparent Power (VA) – Combines active and reactive power, showing total electrical demand.

## FAQs

What is the difference between active power and reactive power?

Active power is the real power consumed by the load, while reactive power is the power oscillating between the source and the load.

Is active and reactive the same?

No, active and reactive power are not the same. Active power is the real power used for work, while reactive power is non-working power.

What is reactive power in simple terms?

Reactive power is the power needed to sustain the electric and magnetic fields in electrical systems, without performing useful work.

What is the difference between active and reactive power?

Active power is measured in kilowatts (kW), while reactive power is measured in kilovolt-amperes reactive (kVAR).

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