Do you know what power factor correction is and how it can benefit your company? By learning how to use energy more efficiently, there are practical ways to reduce an organisations electricity bill and save money.


What is Power Factor?

Did you know when you have electrical energy coming into an installation, the total power you pay for consists of both working power and wasted power (see example of pint of beer below).

To make sure you are using as much working power as possible, we use a calculation technique called power factor, which measures the energy difference between the working power and the total power. The following example helps to explain this and shows that you don’t expect to waste money on purchasing a pint with a lot of head. It is more desirable to have a pint of beer with as little head as possible because you still get charged the same for that pint/ unit if it is useful to you or not.

It is the same with your energy, you don’t want to be paying for 100% energy when you’re only getting 70%. Through power factor correction you can identify how to achieve close to 100% of the energy you pay for and help to reduce wasted energy.

Beer Analogy and Power Triangle



What are the causes to a poor power factor?

Poor power factor is caused by large inductive loads which absorb the working power within an electrical system, causing the power to lag. The following list provides examples:

  • Motors
  • Transformers
  • HVAC systems
  • Presses
  • High-intensity discharge lighting
  • Induction generators

What is your current power factor and where can you find this information?

“It is not uncommon for industrial installations to be operating at power factors between 0.7 and 0.8 – which is relatively poor.” (The Carbon Trust)

The ideal ratio power factor should be operating at between 0.95 to 1.0.

To understand what power factor your installation is running at, you can find your power factor information in the following areas:

  • Utility bills: Depending on the contract, some suppliers may charge for reactive power use, and/or add a fee for poor power factor.
  • Power factor surveys: Power engineering specialists and electricians can conduct a survey to check for poor power factor.
  • Equipment specifications: Nameplates or specification manuals could include power factor specifications. Be cautious about in the way they represent the figure – some may show the figure for power factor, while some will just show the angle.

What is Power Factor Correction?

Power factor correction (PFC) techniques aim to increase and optimise the amount of working power, by reducing and compensating for wasted power in the circuit. These techniques will help to make sure your power is used effectively and help you reduce losses.

 Benefits of PFC

With power factor equal to 1 or as close as possible, there are lower losses and all power generated is utilised efficiently, therefore you will only be paying for power used.

  • Technical benefits: Improved efficiency and reduction in power demand, hence a reduction in the load on the switching gear and cables, reduced costs to the consumer and support for more load.
  • Commercial benefits: There are reduced system losses and less capital cost for the generating company. In addition, there are saving on electricity costs, since there are no charges for the excess reactive power. Another benefit is that the transmission and distribution equipment and systems run cooler and last longer.
  • Environmental benefits: Reduced CO2 emissions.
  • Financial benefits: Save money through reducing your energy bill. In addition, the amount of money you invest in improving power factor correction will deliver a quicker payback for poor installations.

 How can Ayjay Group help?

Over time installations can degrade and require updating. Specifically, if your installation is over 20 years old or if the layout has changed, it is worth checking your equipment to make sure potential issues are corrected.

Ayjay Group can help you understand your power factor and help give you practical advice on how to improve your energy usage.

We can conduct a site survey and investigate any potential issues and check the power factor on site. Our experienced engineers will then advise on the suitable installation/ upgrading/ replacement/ maintenance of equipment, if required, to help you achieve optimum energy efficiency.


For further information, contact our team on 029 2088 7222 or email