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Ban low power factor switch-mode power supplies?

I

ITSME.ULTIMATE

Jan 1, 1970
0
It may not have been 15 years ago, but computers are rather significant
power users.

Modern PCs are gaining in processing power as well as electrical
consumption. It isn't unusual for today's high performance PCs to draw
250-300W of power in its idle state and 400-500W with the CPU and video
card fully loaded.

Computer power supplies with a power output in the neighborhood of half
a kilowatt is not uncommon and most are rated for a minimum of 300W
output. The average computer power supply is very high in THD and has a
power factor of 0.6 to 0.7 and an efficiency rating of around 75%. With
300W power consumption, each computer represents 430-500VA of highly
harmonic load.

I'm guessing a university and such would have around 1,000 computers
through their campus labs which would create around 400 to 500kVA of low
power factor load that power factor correction capacitors can not touch.

Computers in homes don't produce as much of concentrated high harmonic
loads, but rectified input draw is quite a significant part of load on
the power distribution facilities.

There is already a power factor regulation for fluorescent lights and as
a result, many electronic types of ballast have a power factor rating as
high as 0.95-0.99.

http://www.eere.energy.gov/buildings/appliance_standards/residential/pdf
s/lampballast_rule_091900.pdf

Why can't they put a ban on computer power supplies and other high VA
non-sinusoidal appliances such as a big screen TV with an absolutely
lousy power factor and disgustingly high harmonics?
 
C

Charles Perry

Jan 1, 1970
0
ITSME.ULTIMATE said:
It may not have been 15 years ago, but computers are rather significant
power users.

Modern PCs are gaining in processing power as well as electrical
consumption. It isn't unusual for today's high performance PCs to draw
250-300W of power in its idle state and 400-500W with the CPU and video
card fully loaded.

Calm down. Go here:

http://www.efficientpowersupplies.org/

The EPA and California Energy Commission are already on the job.

Charles Perry P.E.
 
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