Client here in New Orleans is getting hammered by Entergy's demand ratchet provision. Set a new peak of 340 kW back in July when two chillers failed and we had to bring portable units online quickly. Now we're paying ratcheted demand charges of 80% of that peak for the next 11 months even though normal load is only 220 kW. That's costing us an extra $1,800 per month. What strategies work for managing demand with unreliable HVAC equipment?
Entergy Louisiana demand ratchet killing us - HVAC strategies?
That ratchet clause is brutal. AEP Texas has similar provisions. Best defense is redundancy and maintenance. We keep spare parts for critical components and have service contracts with 4-hour response times. Also installed a smaller backup chiller that can handle partial load without creating huge demand spikes. Costs more upfront but avoids these ratchet disasters.
CPS Energy has ratchets too but only for 6 months. Key is having an emergency plan before you need it. We keep a list of non-essential loads that can be shed quickly - decorative lighting, water heaters, non-critical exhaust fans. When HVAC fails, we immediately start shedding other loads to minimize the total demand spike. Saved us from a bad ratchet situation twice.
Duke Energy's ratchet is 12 months at 80% here in Charlotte. We use demand controllers with override capability. During normal operations they limit HVAC startup to stay under target. But facilities staff can override during emergencies. The key is training people to think about total building demand, not just getting the cooling back online as fast as possible.
Georgia Power offers demand response credits that can offset some ratchet pain. If you can curtail load during their peak events, they pay you back. We earned about $3,200 last year just by participating. Won't eliminate a ratchet situation but every bit helps when you're stuck paying elevated demand charges for months.
TVA's ratchet is only 6 months thankfully. But we learned the hard way that portable chillers are demand killers. Now we have a small permanent backup system that's much more efficient. Also installed monitoring that alerts us before we hit 90% of our target peak. Gives us time to shed non-critical loads before setting a new ratchet.
Evergy has similar ratchet provisions. We've started using ice storage systems for clients with unreliable HVAC. Make ice at night when demand charges don't matter, then use it for cooling during peak hours. If your main chiller fails, you still have cooling capacity without the massive demand spike from emergency equipment.
Ice storage is interesting but probably too expensive for retrofit. We're looking at a smaller permanent backup chiller instead of relying on portables. Even a 50-ton unit would handle partial load without the crazy power draw. Also considering a preventive maintenance contract to reduce failure risk in the first place.
Ameren Missouri has 12-month ratchets too. One thing that helped us was installing individual meters on major HVAC equipment. When something fails, we can see exactly how much demand each piece is drawing and make smarter decisions about what to bring online. Knowledge is power when you're trying to avoid ratchet hell.
MLGW here in Memphis has ratchet provisions on our larger rate schedules. The key is documentation and planning. Keep detailed records of equipment failures and response procedures. Some utilities will waive ratchet charges for documented emergency situations beyond your control. Worth asking about if you haven't already.
Randy makes a good point about documentation. Entergy actually waived part of our ratchet when we provided maintenance records showing the chiller failure was due to a manufacturing defect. Still paying elevated charges but not the full amount. Always worth appealing these situations with proper documentation.