As many Indian states shift to KvAh-based billing, power factor has become the buzzword in the industry. Power factor plays an important role in the new billing approach. Understanding this term could help a consumer to considerably save their power costs.
The present article discusses what is power factor, and the reasons behind low power factor that could drive your energy costs higher.
What is power factor?
When a machine such as a motor starts, it pulls a certain amount of power just to get started. This is extra power that the load does not actually need to carry on its regular work, This power is called reactive power. After it powers on, the motor will do some actual work, The energy it uses for its actual work is called active power. Lastly, the sum total of reactive and active power is called apparent power.
Power factor is the ratio of active power (measured in kW) to apparent power (measured in KvA) and is expressed in KvA units. It is calculated using the formula
PF= Active power / Apparent power
Power factor is expressed in percentage. The higher the power factor, the more efficient the utilization of power.
The power triangle
The three elements that make up the power factor can be represented graphically as a right-angled triangle.
Where Φ is the phase angle in degrees. The larger the phase angle, the more is the reactive power in the circuit.
How a lower power factor affects the consumer
- Heat damage to electrical equipment and cable insulation
- Requirement of higher sizes of cables and electrical equipment
- Lower availability of active power to do actual work.
Hence, a lower power factor requires a higher current to be supplied from the utility for equipment to run. This results in higher power costs.
What are the reasons behind a lower power factor?
Inductive loads
Most industrial machinery consists of single or three-phase inductive machines. These machines draw magnetizing current which creates a magnetic field, reducing the power factor
Variations in power loading
If the system is only lightly loaded, the voltage increases, leading the equipment to draw more current. This in turn reduces the power factor.
Improper wiring
Improper wiring results in a condition known as three-phase power imbalance which lowers the power factor.
Harmonics
Nonlinear loads such as VFD motors AC units and even computers and UPS generate harmonics. These harmonics introduce distortion reactive power into the electrical circuit, which lowers the power factor.
Conclusion
The power factor of an industrial establishment should be as close to unity as possible. If the power factor is low, it results in power losses throughout the utility lines and transformers. The utility companies then penalize the consumer for these losses, increasing the power costs.
Newtek digital multifunction meters enable the consumers to accurately monitor power factors, harmonics and other key power quality parameters. This data can then be used to improve the power factor and reduce energy costs. For more information on how digital multifunction meters could help you reduce KvAh based power bills, explore our blog here