I've got a client on JEA's GS-2 rate in Jacksonville with a 26-day billing period last month. The demand charge shows $1,847 but when I calculate it manually using their published rate of $8.50/kW and actual demand of 285 kW, I get $2,422.50. That should be prorated to 26/30 which gives me $2,099.50. They're showing $252 less than what I calculate. Am I missing something in the tariff or did they mess up the proration?
JEA prorated demand charges wrong - am I missing something?
Rob, check if there's a minimum billing demand in the tariff. TECO here in Tampa has a clause where billing demand can't be less than 80% of the highest demand in the previous 12 months. If JEA has something similar, that could explain the difference. Also verify they're using the right rate - sometimes there are seasonal variations or fuel adjustments that aren't obvious.
Vernon, good catch. I checked and there is a ratchet provision - billing demand is the higher of actual demand or 85% of peak demand from the past 11 months. The peak was 218 kW, so 85% would be 185 kW. Since actual demand was 285 kW, they should use 285 kW. But wait, looking closer at the bill, they show billing demand as 217 kW, not 285 kW. That's where my calculation went wrong.
Rob, that's weird that billing demand would be less than actual demand unless there's something else in the tariff. PG&E here in Bakersfield sometimes has power factor corrections that reduce billing demand, or there might be credits for load factor or time-of-use considerations. Check if your client has any power factor issues or if JEA has load factor incentives on GS-2.