There are two forms of power. One is real power that can be translated into actual work typically measured in watts. Another is reactive power that is consumed by a device but does not produce any useful work. The sum of both forms of power is the power supplied by a utility.
Power factor of an AC device like CFL ranges from 0 to 1. Closer the power factor of a machine is to 1 the lesser is the distortion in power.
Unlike GLS bulbs that use power as supplied by the utility, CFLs tend to draw power in bursts, which causes distortion in the current wave form also known as harmonic distortion. Harmonic distortion can lead to distorted voltage wave form, thereby reducing power quality. Research on losses due to low power factor commissioned by the New Zealand Electricity Commission concluded that for a utility to correct distortion caused by low power factor it would need to spend about $4 per 20 CFL bulb. However, the power factor does not affect the light output of a CFL or electricity bills of consumers. It leads to higher costs of transmission and distribution of electricity.
There are no regulations on power factor anywhere in the world. Like India, Vietnam too is assessing the problem of low power factor bulbs. New Zealand