A “low power factor” is a common occurrence in industrial complexes. This refers to an inefficiency in the power system, which causes some of the electricity that’s provided by the electric company to be wasted. In addition to the extra cost – including a potential penalty from some utility companies – a low power factor can cause equipment overloads and voltage drops, putting undue strain on this equipment and reducing service life.

Understanding Power Factor

There are three types of power in industrial electrical systems:

1.   Real (or active) power: Power that does useful work.

2.   Reactive power: Nonworking power that is used to create a magnetic field, which in turn is used to facilitate useful work.

3.   Total (or apparent) power: The combination of real and reactive power, which is the actual power used by your industrial facility.

Power factor is a measurement defined as the ratio of real power to total power. In other words, power factor measures the percentage of power that is being used for useful work. When this percentage drops below about 0.95 or 95%, it means that about five percent of the current coming from the electrical company is being used for nonworking power, and many utility companies will charge you a penalty fee as a result of this inefficiency.

What Causes Low Power Factor?

Low power factor usually is caused by inductive loads, such as:

• Electric motors
• Transformers
• Arc welders
• HVAC systems
• Molding equipment
• Presses
• High-intensity discharge lighting

Unlike resistive loads (i.e., incandescent lights, electric heaters, cooking ovens), which involve a more direct conversion to useful work in the form of heat energy, inductive loads operate off of the magnetic field that is created by reactive power.

What Are the Benefits of Improving My Power Factor?

There are many benefits to improving a low power factor, including:

A smaller utility bill. By correcting your power factor, you can reduce the amount of reactive power needed to run your facility, thus lowering your electric bill. You can also avoid any potential penalty fees from your utility company.

An increase in electrical system capacity. A low power factor causes a greater loss of power in your electrical distribution system.

Fewer voltage fluctuations. An inefficient system with power losses can result in equipment overloads, overheating and a shorter service life.

How Can I Correct My Power Factor?

While low power factor can cause a significant increase in your plant expenses and a decrease in your system’s efficiency, you can take several steps to help correct your power factor, including:

• Minimizing the operation of idling or lightly loaded inductive equipment, particularly motors
• Replacing defunct motors with energy-efficient ones, and operating these near their rated capacity
• Avoiding operating your equipment above its rated voltage
• Installing capacitors to decrease the amount of reactive power used

New Electric can provide the assistance you may need to assess the many ways you can improve your power factor, and to correctly locate and install capacitors in your electrical distribution system.