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Power Factor Correction devices ensure that your equipment is running at its optimum level.

Power Factor Correction devices ensure that your equipment is running at its optimum level.

By Dan Parsley, EES Consulting
Originally posted on Furniture World

Even though you pay for it, a portion of the power entering your electrical system is never consumed. Many furniture retailers and manufacturers can benefit from installing a power factor correcting (PFC) device that reduces your facility’s inductive load and reduces this wasted energy.

What is Power Factor?
In layman’s terms, “power factor” is a numerical measure of how efficiently the devices in your facility are consuming electrical power. Power factor is measured on a scale of 0 to 1, expressed in percent or decimal format, with 1.0 as the ideal ratio of power drawn from the network vs. power used to accomplish tasks. Fall below 0.90 or above 1.0, and your utility company may penalize you with extra monthly fees.

What Causes Low Power Factor?
Low power factor is caused by inductive loads. This includes any equipment that requires a start-up mechanism, such as transformers, compressors, computers, fluorescent and high-intensity discharge lighting, and electric motors like those on air conditioners.

Pertaining to these devices, “real power” is the electricity that’s actually doing the work, like keeping your lights on and keeping the refrigerant moving in the air conditioning system. A second component, “reactive power,” is the energy that’s required to magnetize the devices and does not contribute to achieving the task.

The ideal 1.0 or 100 percent ratio indicates a perfect match between power drawn from the grid and real power needed to complete the actual work. The more reactive power you are using, the lower your power factor ratio.

Why Improve Your Power Factor?

Poor power factor can have several negative implications for your business, according to The Carbon Trust:

  • You may incur a “poor power factor penalty” or “reactive power charge” from the utility;
  • You will draw more energy from the network, costing you more to achieve the same tasks;
  • Low power factor reduces the effective capacity of the electrical supply;
  • Low power factor causes great loss at the transformers and other inductive loads, leading to inefficiency and unwanted heat dissipation;
  • A good power factor reduces excessive voltage drops in the supply network; and
  • In extreme cases, low power factor will reduce the life expectancy of costly electrical equipment.


Correcting Your Power Factor

A PFC device consists of capacitor banks that decrease the magnitude of the inductive reactive power. The capacitors uphold the voltage of the inductive load, making the equipment more efficient. The more efficient equipment reduces the energy drawn from the electric utility, lowering your electrical bill.

Is a PFC Device Right for Me?
Power factor correction is not a one-size-fits-all solution. First, start by carefully reviewing your energy bill or hiring an electrician or consultant to determine whether your business or manufacturing facility has a low power factor ratio.

Only consider a PFC device if the readings from your distribution panel indicate that it would be economically justifiable. If you are already at a 0.90 or 0.95 in your facility, you run the risk of over-correcting and incurring penalties on the opposite end. An energy efficiency professional can help you select the right size and design of a device to ensure maximum savings and a quick payback for your facility.

Written by Dan Parsley

Dan Parsley is the President and COO of EES Consulting.

Dan Parsley is the President and COO of EES Consulting.