We got blindsided by an $18,000 power factor penalty from Oncor last month on our Schedule LPS-2 account. Our automatic correction banks were running the whole time - I verified the logs myself. The penalty was calculated on readings showing 0.74 lagging PF during peak hours in July. Has anyone else seen Oncor's meters give bad PF readings when the correction equipment is clearly functioning? I'm wondering if their new AMI meters have calibration issues with reactive power measurement.
Oncor hit us with $18K power factor penalty - equipment was working!
Marcus, we had something similar with Georgia Power two years ago. Turned out their meter wasn't picking up our switched capacitor banks because they were cycling too fast. The utility's 15-minute interval averaging missed the correction cycles. We had to install a different controller with longer hold times. Did you check if your banks are switching during Oncor's measurement window?
Rachel makes a good point about the timing. Alabama Power uses 15-minute demand windows too, and we've seen banks that switch every 5 minutes cause measurement errors. Also check if you have any single-phasing issues - that can throw off PF calculations even with working correction equipment.
Had this exact issue with PSO here in Tulsa. Their Schedule LP tariff has the same 0.85 PF requirement as Oncor. The problem was our correction banks were sized for the old load profile, but we'd added new equipment that shifted our reactive power pattern. The banks were correcting at the wrong times. Worth checking your load studies against current operations.
Marcus, before you pay that penalty, demand to see Oncor's interval data. Under PUCT rules, they have to provide detailed reactive power measurements if you dispute the bill. I've gotten penalties reversed when the utility couldn't justify their readings. Also, check if they're using the right tariff - some facilities get mis-classified and hit with industrial PF requirements when they should be on commercial schedules.
Phil, that's great advice about the interval data. I requested it yesterday and Oncor is dragging their feet. Ed, you might be onto something about the load profile - we did install three new injection molding machines in May. The reactive load from those could be throwing off our correction timing. Going to have our electrical contractor do a new power study this week.
Keep us posted on how this turns out. Duquesne Light has been getting more aggressive with PF penalties lately, and I want to know if other utilities are following suit. An $18K hit is no joke - that's worth fighting even if it costs a few grand in engineering fees to prove your case.
UPDATE: Got the interval data from Oncor and Phil was right - they were using the wrong billing determinant. Our facility should be on Schedule LPS-1, not LPS-2. The PF threshold is different and we would have been compliant. Filing a formal dispute with PUCT this week. Thanks everyone for the input!