Typical Utility Power Factors

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spsnyder

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What is the "typical" power factor delivered by the utilities. Realizing I'll take a beating on the term "typical" I was wondering about the low end range. Could it be as low as 0.8, 0.7, 0.6 or lower? I assume the Po Co's have power factor correction stations dispersed periodically. Is that correct?

Thank you in advance.
 
Utility companies try to generate as close to 1.0 as possible, they only get paid for the Watts, not the Vars. Typically, they will charge a customer for a plant pf lower than 0.85 because it costs them money to push Vars out onto the system.

You are also correct that they have cap banks, but they are used for voltage support, not specifcally for VAR support or pf correction.

You could use 0.85 for your calcs, but that would be the bottom of the rung, so to speak.
 
Thanks for the info. I work at a very large facility and about fell off my chair when I was informed we have a pf of ~0.5. We consume more reactive power than real power. I wondered how far from unity the utility's pf could be.
 
spsnyder said:
I work at a very large facility and about fell off my chair when I was informed we have a pf of ~0.5. We consume more reactive power than real power. I wondered how far from unity the utility's pf could be.
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You can calculate the vars needed to get to unity PF. If you are being billed
on a KVA demand, it is well worth you time and money to correct the PF
to 0.95 or higher. You should be able to get the kw and pf from the utility.
If you are only being billed for kw then you have another decision to make.

spsnyder said:
What is the "typical" power factor delivered by the utilities. Realizing I'll take a beating on the term "typical" I was wondering about the low end range. Could it be as low as 0.8, 0.7, 0.6 or lower? I assume the Po Co's have power factor correction stations dispersed periodically. Is that correct?
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That is a strange question. The utility does not control the PF of the customers. They will deliver what ever the customers demand. The utility
makes PF correction mainly at the substation. Additional correction is made
with online capacitors if needed. These online caps also serve to reduce the
voltage drop on the feeder.
 
Bob is correct. PF is a function of the load characteristics. Plus, it benefits you to have the correction devices attached as close to the offending equipment as you can.

I'd ask a few questions, such as where on the system, and how, this measurement was taken. That's a very difficult PF to acheive even if you're trying to.
 
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The utility company does not have a power factor to speak of since it is in the delivery business and not the usage business.
Most utilities bill for bad PF at peak demand. If you are seeing .5 on peak you have a lot of unloaded motors such as a flywheel UPS or similar loads.

Power company want to squeeze as much power into thier lines as possible that they can bill for so they are very close to 1.0.
 
At our company we will bill you for less than .85. I have to maintain a system PF of .95 lagging on peak, I can't lead at all on peak as that is a penalty also.
Off peak I have to be .95 lagging or better also and again can't lead at all. Back when our supplier (TVA) didn't have enough caps on their system to hold their system up during peak conditions they let us lead all we wanted during the summer months to help them.

I think you are right in saying that the distributor doesn't supply a PF to a customer the customer generates that themselves. We supply KWH,KW,KVA, and KVAR to the customer if they request it, there is no telling how many letters I have sent out to customers stating they could save money by adding caps and the payback would be extremely quick also. I think I could make a good living if some would let me install them at my expense and just take half the savings of the bill each month. We penalize our customers at .85 PF.

I have spent several thousand dollars getting caps under scada control at each breaker in all stations we have and wrote a script that monitors the PF at the station and brings the caps on and off as needed. The payback for this is very,very, short compared to the penalties involved.

I would contact my supplier and ask them to help with the PF correction and I bet they got somebody that will come out and give pointers for ya at no cost, after all it helps them and makes their job easier also.
 
Thank you all for your great responses. I've been away for several days. I don't have any control/authority when it comes to the utility end of the system. I have passed on my thoughts on the matter to those who are responsible for that end. I think this is a classic No-Brainer to fix the extremely lagging power factor. We'll see....
 
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