Had a restaurant chain client getting hit with power factor penalties from Duke Energy Ohio. Looked like a straightforward case - install capacitors and problem solved. Spent three months going back and forth with the client about capacitor installation. Finally discovered the real issue was their walk-in cooler compressors cycling on during peak demand periods and creating harmonic distortion. The power factor penalties were actually a secondary effect of the harmonics. Sometimes you have to dig deeper than the obvious solution.
Power factor penalties - when the obvious isn't so obvious
Cecilia that's a great point about harmonics. I've seen similar issues here in Memphis with MLGW. Variable frequency drives on HVAC systems can create power quality issues that show up as power factor problems on the bill. Always worth checking the actual power quality measurements before recommending solutions.
Had a Nashville client with TVA service getting power factor penalties. Turned out their penalty was actually coming from reactive power during light load periods, not heavy load. Their capacitors were over-correcting at night when the motors weren't running. Had to install automatic capacitor switching to solve it properly.
Holly that's exactly the kind of thing that trips us up. We see power factor penalty and immediately think "add capacitors" but sometimes you need less correction, not more. I've learned to always ask for interval data showing reactive power patterns throughout the billing period.
Kentucky Utilities has some unusual power factor calculation methods that caught me off guard once. They use a sliding scale penalty that changes based on your total kWh usage. Higher usage customers get more lenient power factor requirements. Almost recommended unnecessary equipment because I didn't read the tariff carefully enough.
Portland General Electric has been really strict about power factor lately. But I learned that they'll waive penalties if you can demonstrate that the low power factor is caused by equipment that serves a critical safety function. Documentation is key - had a client avoid $12K in annual penalties by proving their low power factor came from required emergency lighting systems.