What is Ballast Efficacy Factor (BEF)

Horace He

Last Updated: August 14, 2023

What is Ballast Efficacy Factor (BEF)

Ballast Efficacy Factor (BEF) is a metric used in the lighting industry to evaluate the energy efficiency of ballasts. It is calculated by dividing the ballast factor by the input watts. The ballast factor represents the ratio of the light output of a lamp or lamps operated on a specific ballast to the light output of the same lamp or lamps operated on a reference ballast. By dividing this value by the input watts, the BEF provides a measure of the energy efficiency of the ballast.

The BEF is particularly useful for comparing the energy efficiency of different lighting systems that operate the same type and quantity of lamps. It allows for a standardized assessment of the light output and power input of these systems. The BEF is specific to the North American energy standards for fluorescent ballasts. Other regions or lighting technologies may use different metrics to evaluate energy efficiency.

Frequently Asked Questions

What Is the Difference Between Power Factor and Ballast Factor

Ballast Power Factor is a measure of how effectively a ballast utilizes its power. It is expressed as a percentage, ranging from 0% to 100%. Power factor represents the ratio of power consumed by the ballast to the total power provided by the utility. The formula for calculating power factor is Watts divided by Volt-Amperes.

What Type of Ballast Has the Highest Efficiency

The ballasts with the highest efficiency are electronic or high-frequency ballasts. These types of ballasts are known for boosting the frequency of electricity from the standard 60 cycles per second (hertz) to a much higher range, typically between 25,000 to 40,000 hertz.