What is power factor correction and how can it save energy?

For commercial business owners, understanding your energy consumption is essential. When evaluating the performance of a building, the main goal is always to reduce energy consumption and costs wherever possible. However, one aspect that is often overlooked in this process is the power factor.

Power factor is a measure of how effectively electrical power is converted into useful work in an electrical system. Improving the power factor with power factor correction can lead to energy efficiency and savings in commercial businesses.

In this blog, we look at what is power factor correction and how it can lead to power factor energy savings.

What is power factor correction?

Before we explain what power factor correction is, it is important to understand how electricity is used in a system and power factor.

The electrical energy used in a system is comprised of two components: Real Power and Reactive Power. Real Power, measured in kilowatts (kW), is the actual power consumed by devices to produce outcomes like heat, light, and motion.

Reactive Power, measured in kilovolt-amperes reactive (kVAR), supports and sustains the voltage levels within an electrical system, enabling the efficient operation of inductive loads such as motors and transformers. Together, these two types of power constitute Apparent Power.

Every machine has an efficiency metric called the power factor. The power factor is a measure of how efficiently electricity is being used. It is a ratio of Real Power to Apparent Power, shown in a metric that ranges between 0 to 1. A power factor should be 1, which means 100% efficiency.

The more inductive the load(s), the greater the chance for a lagging power factor, which will result in a power factor lower than 100%. The more capacitive the load(s), the greater the chance for a leading power factor, which is closer to 100%.

Power factor correction is the method to improve an electrical system’s power factor, bringing it closer to 1. Power factor correction enhances the system’s efficiency, ensuring that the electricity consumed is used most productively.

How can power factor correction save energy?

Power factor correction is designed to conserve energy. When the power factor in a system is less than 1, more current is needed to deliver the same amount of Real Power to devices.

By adjusting the power factor closer to 1 through power factor correction techniques, the system can reduce the amount of wasted Reactive Power. This means electrical devices can operate more efficiently with less current, resulting in lower energy consumption.

How is power factor correction installed?

Power factor correction is achieved by installing capacitors into the circuit, which help align the voltage and current. Capacitors store and subsequently release energy, balancing any lag in the power factor of the system.

Installing capacitors will not only help your building’s systems store power but also reduce the required reactive power to maintain loads, helping to increase energy savings and reduce costs.

After capacitors are professionally installed, their performance can be tracked using energy management software. This is just one of the many benefits of energy management software.

What are the types of power factor correction?

There are several methods and devices used to achieve power factor correction.

Here’s a breakdown of the most common types:

  • Passive Power Factor Correction (Passive PFC): In this method, corrective components like capacitors and inductors are placed in series or parallel with the load circuit. It’s simpler than active PFC but may not be as effective for all load conditions.
  • Active Power Factor Correction (Active PFC): This is a method used primarily in electronic power supplies. Using active electronic components like transistors and microcontrollers, it dynamically adjusts the incoming power to achieve a power factor closer to 1.

Each of these types has its advantages. The choice often depends on the specific needs of the electrical system, the nature of the loads, and cost considerations.

What are the benefits of power factor correction?

Power factor correction is a power factor energy saver that all commercial building owners need to consider to improve their energy efficiency.

We highlight the power factor energy benefits of power factor correction:

Reduction in power consumption losses

Improving the power factor means there are fewer energy losses in the system. This means less energy is wasted and more of it is used effectively. This allows you to save money on energy bills.

Improvement in overall power quality

When the power factor is optimised, the entire electrical framework experiences less strain. This improves the overall power quality. It also ensures extended equipment life and minimal downtime.

Removal of excess charges

Often, electricity providers impose penalty charges for a less optimal power factor. With power factor correction, these additional costs can be avoided, cutting down the overall electricity expenses.

Reduction in circuit currents

Minimising the current drawn from the source due to improved power factor leads to decreased wear and tear on the distribution network. This can lead to reduced maintenance costs in the longer run.

Removal of penalties on electricity bill

Many businesses remain unaware of the penalties levied on their electricity bills owing to inadequate power factors. By rectifying the power factor, these additional charges can be eliminated, resulting in direct financial savings.

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FAQs about what is the power factor correction

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