PF Feasibility 3

[tulum]

I work at a small manufacturing plant in Ontario, Canada. Lately, the price of electricity has increased dramatically. I have been chosen (by the powers that be) to do a feasibility study on installing PFC capacitors (more than likely located at the main panel). Has anyone been through this before, and how should I proceed?

I assume I should log Power, volts, and Amp readings at each piece of equipment (and at the main Panel)? From this I can decide where to place the Caps, and whether they are needed or not. What is a good PF to shoot for? 90%? What is a poor PF to have? 80%? ...Basically what would make this feasible?

There aren't many large loads at the plant (metal shop, paint shop, office). However, loads are old and are probably not too efficient.

Any comments appreciated.

 

[busbar]

The biggest influence on payback is the serving utility’s tariff or rate structure. Careful review is in order. [It is a good application for a spreadsheet.] Another reference is chapter 8 of IEEE Std 141-1993 Recommended Practice for Electric Power Distribution for Industrial Plants

 

[Jerry123]

Getting info on you loading could be performed a couple of ways. One you could get a testing company to monitor the loading conditions. This should be performed for a 30-day duration. Or you could call the utility and ask for the last 12-month billings. On the billings it should have the power factor and the KW or KVA usage.

As for capacitor bank, there are basically two types. A fixed or standard and an automatic or switching.

As for a good PF, 0.9 and above. In my area the utility changes a penalty for have a PF lower than 0.85. The utility north of me gives a reduction off the billing for having a PF greater that 0.9.

Having said that you may want to get your utilities rate structure.

You can also visit

http://www.squared.com

and search for capacitors bank. They have good description of there products.

 

[jbartos]

Suggestion: A good and established reference is:
Donald Beeman "Industrial Power Systems Handbook," First Edition, McGraw-Hill Book Company, 1955,
Chapter 8 by W. C. Bloomquist "Power-Factor Improvement" pages 439-503. It includes:
Power Factor Fundamentals
Instruments and Measurements for Power-Factor Studies
Location of Capacitors and Synchronous Motors
Advantages of Improved Power Factor
Voltage Improvement
Selection and Application of Motors and Capacitors
Selection of Capacitor Switching and Cable Size
Harmonics and Resonance as Affected by Capacitors
Automatic Switching of Capacitors
Series Capacitors
Capacitor Ratings and Operating Characteristics
Useful Data for Capacitor Application

As it can be seen, the reference covers the capacitor improvement comprehensively.