This is probably my biggest single find to date. Client is a plastics manufacturer in the Research Triangle area, served by Duke Energy on Schedule OPT-V. They had a 2000 kVA transformer with CTs rated at 800:5. When I pulled the meter records and compared to the installed CT configuration, the billing multiplier was set at 80 instead of 160. Someone fat-fingered the multiplier during a meter swap in 2011 and it went the OTHER direction — overbilled by a factor of 2. Client was paying roughly double their actual demand and consumption for almost 4 years before I caught it in mid-2015. Refund came to $127,400 going back to the meter swap date. Duke was actually pretty cooperative once I showed them their own installation records.
Found a CT ratio error — $127,000 refund
That is a textbook CT ratio case. The meter swap is where these almost always happen. I tell every new auditor — first thing you do on any commercial account over 200 kW is request the meter installation records and compare the CT ratio to the billing multiplier. Takes 10 minutes and I have found discrepancies on maybe 1 in 15 accounts.
Nice catch. Question though — when the multiplier error goes the other way (underbilling), does the utility come after the customer for the difference? Had a situation in PNM territory where I was nervous about even mentioning it.
Randy nailed it. In my case it was overbilling so there was no downside risk. Duke actually thanked me for finding it because it cleaned up their records. The client was thrilled obviously. My contingency fee on that one was 30% so I earned about $38K from a single line item on one account. That is the kind of find that keeps you in this business.
I keep a spreadsheet of every CT ratio error I have found. Out of roughly 1,100 commercial accounts I have audited over the years, I have found 73 meter multiplier discrepancies. About 60% favored the utility (overbilling) and 40% favored the customer. The average overbilling amount was around $18K. So yes, this is one of the most productive things you can check.
Walt that is an incredible dataset. Mind sharing what percentage of those were caught during meter swaps vs original installation errors?
Off the top of my head, roughly 70% were meter swap related. The rest were original installation or some kind of billing system migration where the multiplier got entered wrong when they moved to a new CIS platform. Duquesne Light had a whole batch of those around 2008 when they upgraded their billing system.