Client got nailed last month on their AEP Texas bill - HVAC system startup after maintenance created a 347kW demand spike for about 8 minutes. That single event drove their monthly demand charge from the usual $2,200 to $10,600 under Rate Schedule SGS-3. The facility manager said all four RTUs came online simultaneously after the weekend shutdown. Has anyone else seen AEP Texas nail customers this hard for brief HVAC spikes? I'm wondering if we can challenge this since it was clearly an operational anomaly, not sustained usage.
AEP Texas - HVAC startup spike hit us with $8,400 demand charge
Vivian, that's brutal but unfortunately typical for AEP. I've seen FirstEnergy here in Cleveland do similar things but usually not quite that severe. The key is proving it was truly an anomaly versus normal operations. Did your client have any documentation of the maintenance work or startup procedures? Sometimes you can get relief if you can show it was due to equipment malfunction or improper sequencing that's since been corrected.
We had a similar situation with CPS Energy here in San Antonio. Manufacturing client had all their chillers kick on at once due to a BMS glitch - 280kW spike that lasted maybe 6 minutes. CPS refused to budge initially but we filed a formal dispute with engineering documentation showing the malfunction. Took 4 months but they credited back about 60% of the excess demand charges. Key was having the BMS logs and repair records.
Tennessee Valley Authority has gotten more reasonable about these situations in recent years. They'll usually work with you if it's clearly documented as equipment malfunction. But Texas utilities seem much more rigid about their tariffs. Vivian, what's the facility - office building, manufacturing, retail? The type of operation might give you different appeal options under AEP's tariff.
It's a 85,000 sq ft distribution center in Corpus Christi. Four 25-ton RTUs that normally sequence on over 15-20 minutes during normal startup. The maintenance crew apparently bypassed the sequencing controller to test each unit individually, then forgot to re-engage the sequencing before leaving. Monday morning the BMS brought all four online simultaneously. I've got the maintenance logs and BMS data showing the normal startup pattern versus this anomaly.
That sounds like a solid case for appeal. LG&E here in Louisville has a provision for "unusual operating conditions" in their large commercial tariff. Check if AEP Texas SGS-3 has similar language. The key phrase you want to look for is something about charges being "representative of normal operations." If the spike was due to maintenance error that's been corrected, you've got a good argument.
Connecticut utilities are pretty reasonable about this stuff, but I know Texas is tougher. One thing that helped us with a similar case - we had the HVAC contractor write a letter explaining exactly what went wrong and what procedures they've implemented to prevent it happening again. Shows the utility it was a one-time event, not a pattern of poor operations.
Good suggestions everyone. I've drafted the appeal letter with all the documentation - maintenance logs, BMS reports, and a letter from the HVAC contractor explaining the sequencing bypass and corrective actions. AEP Texas has 45 days to respond under their tariff. I'll update this thread when I hear back. Fingers crossed they'll at least give us partial relief on that $8,400 hit.
Hope it works out Vivian. Keep us posted - these precedents help everyone understand how different utilities handle these situations. The more documentation we can share about successful appeals, the better prepared we all are when it happens to our clients.