In an earlier post, we have learned different types of power in electrical circuits with the help of the circuit diagram. Now, in this post, we are going to study the difference between active and reactive power.
What is the difference between Active and Reactive Power?
Let’s compare the two different powers with their specifications and examples in the tabular form.
| Sr. No. | Content | Active Power | Reactive Power |
| 01 | Basic Definition | Active power is the power that continuously flows from source to load in an electric circuit. | Reactive power is the power that continuously flows from source to load and returns back to source in an electric circuit. |
| 02 | Called as | Active power is called as ‘Real power’ or ‘Watt full power’ or ‘True power’or Actual power. | Reactive power is called as ‘Imaginary power’ or ‘Watt less power’ or ‘Useless power’ or Complex power. |
| 03 | Represented by | Active power is denoted by the capital letter ‘P‘. | Reactive power is denoted by the capital letter ‘Q‘. |
| 04 | Formula (Online Power Calculator) | You can calculate the active power (P) by using the below formula. Active Power=[Voltage*Current*Cos(θ)] | You can calculate the reactive power (Q) by using the below formula. Reactive Power= [Voltage*Current*Sin(θ)] |
| 05 | Measuring Unit | It is measured in Watt (W) or Kilowatt (kW) or MegaWatt (MW). | It is measured in Volt Ampere Reactive (VAR) or Kilovolt Ampere Reactive (kVAR) or MegaVolt Ampere Reactive (MVAR). |
| 06 | Measuring Instruments (How to measure active and reactive power?) | For measuring the active power, a wattmeter is required. | For measuring the reactive power, a VARmeter is required. |
| 07 | Power Direction | This power flows in only one direction with resepctive time. | This power flows in both directions with respective time. |
| 08 | Function I | Active power is utilised or dissipated in the circuit through the connected resistive load. | Reactive power is stored in the circuit through the connected inductive load. |
| 09 | Function II | It consumes useful power by the load. | It consumes use less power by the load. |
| 10 | Useful Circuit | It works in both AC and DC circuit. | It works in an AC circuit. |
| 11 | Working Role | It converts electrical energy into other forms of energy like optical, thermal, mechanical. | It does not convert energy. But, it produces the electrical or magnetic flux. |
| 12 | Power Contribustion | In an electrical circuit, active power contributes to the current component which is in the phase with circuit voltage. | In an electrical circuit, reactive power contributes to the current component which is in out of phase with circuit voltage. |
| 13 | Usage | Active power is used in incandescent light, oven, coffee makers, iron, toaster, heater, machine, etc. | Reactive power is used in fan, vacuum cleaner, dishwasher, washing machine, the compressor in the refrigerator, air conditioners, transformer, etc. |
With the help of the basic concepts, functions, and uses, we have differentiated active power and reactive power.
Read Related Comparisons:
- Alternating Current vs Direct Current
- Electric Energy vs Electric Power
- Electrical Circuit vs Magnetic Circuit
- Core Type Transformer vs Shell Type Transformer
- Single Phase vs Three phase
- Synchronous Motor vs Induction Motor
If you have any doubts or queries regarding difference between active and reactive power, ask me in the below comment section.
Thanks for Reading!
I have completed master in Electrical Power System. I work and write technical tutorials on the PLC, MATLAB programming, and Electrical on DipsLab.com portal.
Sharing my knowledge on this blog makes me happy. And sometimes I delve in Python programming.
Very useful for me
VERY CLEAR
THANKS ALOT
Explicit explanation, thanks alot
You’re welcome 🙂
Very informative
Thanks, Akash.