Just got hammered by Georgia Power on our July bill. Client had a 3-ton chiller that kicked on during peak hours and spiked demand to 847 kW for literally 2 minutes. Under Schedule GSD-1, that cost them an extra $4,200 for the month. The chiller contractor said the soft start was 'working fine' but clearly something went wrong. Anyone else seeing these kinds of spikes from HVAC startups? This is getting ridiculous.
Georgia Power demand spike from chiller startup - $4,200 hit!
Derek, I see this all the time here in Knoxville with TVA industrial rates. The problem is most HVAC contractors don't understand demand charges at all. They install equipment that meets cooling specs but ignore the electrical impact. I've had clients get hit for $8,000+ from a single startup event. You need to get an electrical contractor involved, not just HVAC. Soft starts fail more often than people think.
This is exactly why I always recommend demand monitoring for any facility with chillers over 100 tons. Georgia Power's Schedule GSD has that nasty ratchet provision too - you'll be paying elevated demand charges for months. Have you checked if the client qualifies for the interruptible rate rider? Might offset some of the damage going forward.
Frank here from Cleveland. FirstEnergy has similar issues but we see it more with rooftop units cycling simultaneously. Had a strip mall where 12 RTUs all kicked on within 30 seconds during a hot afternoon. Demand went from 180 kW to 425 kW instantly. Cost them $2,800 extra that month. The solution was staggered start controls - spread the startup over 5 minutes instead of all at once.
Jack in Louisville here. LG&E just changed their demand window from 15 minutes to 5 minutes on commercial rates. Makes these HVAC spikes even more brutal. I'm telling all my clients to invest in proper sequencing controls now, before they get burned. The payback is usually under 6 months when you consider demand charge exposure.
Amir here from Memphis. MLGW's GSA-2 rate has been brutal this summer. I had a client with a 50-ton chiller that failed its soft start during a 98-degree day. Demand spiked to 312 kW from their normal 185 kW. Between the demand charge and the ratchet, it'll cost them about $3,600 over the next three months. The facility manager had no idea this was even possible.
Thanks everyone. I'm definitely pushing for demand monitoring and proper sequencing controls. The crazy part is the chiller manufacturer claimed their soft start was 'industry standard' - apparently that doesn't include understanding utility rate structures! Going to make sure the electrical contractor specs everything with demand charges in mind going forward.