Just wrapped up an audit where I completely missed a massive demand billing error. Client had been getting charged peak demand during off-peak hours for 14 months. LG&E was applying Schedule LGS-TOU incorrectly but I focused only on energy charges in my initial review. Cost my client $18,347 in overcharges I should have caught. Anyone else have stories of expensive oversights early in their career?
Missed $18K in demand charges - rookie mistake
Been there Jack. My second year doing this I missed a power factor penalty that had been running for 8 months. FirstEnergy was charging the client an extra $1,200/month because their PF dropped below 0.85 but I didn't even know to look for it. The penalty was buried in a tiny line item. Learned to always check every single charge code after that embarrassment.
ComEd got me good in my first year. Spent weeks analyzing energy usage patterns but never verified the rate schedule classification. Turns out they had the client on Schedule 6L when they should have been on 4L. Six months of billing at the wrong rate structure. $24K mistake that still makes me cringe. Now rate schedule verification is step #1 on every audit.
The worst is when you think you found everything and then discover something huge later. Had a Duke Energy account where I caught $8K in energy billing errors but missed that they were being double-charged for street lighting service. That was another $12K over 18 months. Client wasn't happy I had to go back with a revised report.
Georgia Power taught me to read the fine print. Client was on Schedule PL-1 but had a special contract rider that modified the demand charges. I calculated refunds based on the standard tariff and was off by $15K. The rider was mentioned in one sentence on page 2 of a 4-page service agreement. Now I read every word of every contract.
Xcel Energy in Minneapolis had me fooled with their seasonal rate adjustments. I was calculating summer demand charges using winter rates because I didn't realize the tariff had different periods. Three months of bills analyzed completely wrong. Thankfully caught it before submitting the report but felt like an idiot. Always double-check seasonal variations now.
Alabama Power almost cost me a client. Missed a transformer ownership credit that was worth $400/month. It was listed as "TO Credit" and I had no idea what it meant so I ignored it. Client found out from another auditor later. Lesson learned: if you don't understand a charge, research it or ask. Never assume it's not important.
Thanks for sharing these stories everyone. Makes me feel better about my own mistakes. Duke Energy in Charlotte had me chasing my tail for weeks because I was using the wrong effective date for a rate change. Calculated everything based on old rates. These experiences definitely make you more thorough going forward.