Power Factor Correction

The quantity of electric motors, induction heaters, and fluorescent lighting installation in commercial and industrial buildings has increased significantly, reducing the power factor and the efficiency of the electrical supply.

Utilising power factor correction reduces the reactive current drawn from the electrical supply, reduces/removes reactive power charging, reduces CO₂emissions, reduces kWh consumption and creates greater supply capacity through more efficient energy use. In carbon terms, 95kg of CO₂ is saved for every kVAr of power factor correction installed.

An additional incentive for building operators is an adjustment factor of 0.025 in calculation of the Building Emissions Rating within the Building Regulations Part L for optimisation of the power factor to 0.95.


Power factor is simple

Power factor is one of the most misunderstood areas of electrical engineering, yet it is really very simple. Plant and equipment most likely to contribute to poor power factor are those requiring the creation of a magnetic field to operate, such as electric motors, induction heaters and fluorescent lighting. All these types of devices draw current that is said to lag behind the voltage, thus producing a lagging power factor.

Capacitors, used in most power factor correction equipment, draw current that is said to lead the voltage - hence producing a leading power factor. If capacitors are connected to a circuit that operates at a nominally lagging power factor, the extent that the circuit lags is reduced proportionately. Circuits having no resultant leading or lagging component are described as operating at unity power factor and therefore the total energy used is equal to the useful energy.


Power Factor Correction components - Panelbuilders


 > Saving energy & money is made easy with A J Hurst

To find out more about our range of products and services please call us on +44 (0) 28 9077 0037 




Unit 10 Graham Industrial Park, Dargan Crescent, Belfast BT3 9BW Northern Ireland Tel: +44 (0)28 9077 0037