Why is the Power Factor (PFC) value listed on most modern PSU units?

Why is the Power Factor (PFC) value listed on most modern PSU units?

• It indicates the level of efficiency of the PSU
• It points to the materials used in the PSU (Gold, Silver etc)
• It relates with the thermal resistance properties
• Indicates coeficient for the longevity of the PSU 

 

EXPLANATION

The Power Factor value shows the efficiency of the power unit. The power unit capabilities are usually stated as W consumed by the unit (kVA). How much of this power will be available to the loads attached to the PSU however is dictated by the its conversion capabilities summarized by the PFC value. For example, a 1000W PSU with a PFC factor of 0.9 will be able to supply a total of 900W to it's loads.

The PFC itself measures the alignment of the the voltage sinusoidal against the current sinusoidal. If they match 100% you would get a PFC of 1 and hence the perfect lossless PSU. In realty >0.95 is hardly achieved and considered very good while 0.8 could be considered as average PSU. 0.7 is considered as a bad performing PSU