Just finished an audit for a manufacturing client in Wichita with a 500kW solar array under Westar's net metering tariff. Found they've been billing the customer incorrectly for 18 months on the monthly true-up calculations. The utility was applying the retail rate to excess generation instead of the avoided cost rate per Schedule NM-L. Client was overcharged $8,400 and counting. Anyone else seeing issues with Westar's net metering billing? Their customer service claims this is how they've always done it, but the tariff clearly states otherwise.
Westar Net Metering True-Up Billing Error - $8,400 Overcharge
Rachel, we've seen similar issues with other utilities in the Midwest. WE Energies here in Wisconsin had a systematic error in their net metering calculations that we caught on three separate audits last year. The key is getting them to acknowledge the tariff language vs their billing practice. Did you file a formal complaint with the Kansas Corporation Commission? That usually gets their attention faster than going through customer service.
This is exactly why I always scrutinize the net metering calculations on solar audits. Idaho Power had a similar issue with their Schedule 84 tariff where they were miscalculating the monthly carryover credits. Found it on a food processing plant in Nampa - they owed the customer $12,000 in billing adjustments. The utility's billing system wasn't properly configured for the tariff's seasonal rate differentials. Documentation is everything in these cases.
Dan, yes we're preparing the KCC complaint now. The utility is claiming their interpretation is correct, but Schedule NM-L section 4.3 is pretty clear about avoided cost vs retail rate application. Stan, that Idaho Power case sounds identical - was their issue also in the billing system configuration or was it a policy interpretation problem? I'm trying to determine if this is widespread incompetence or intentional.
Rachel, in our case it was definitely a billing system issue. The programmer who configured the net metering module didn't understand the tariff's seasonal credit calculations. Once we showed them the error with specific bill examples, they fixed it within 30 days and issued refunds. But it took finding three separate customers with the same error before they'd admit it was systemic. Keep pushing - $8,400 is significant money.
We've been dealing with MLGW here in Memphis on similar net metering billing discrepancies. Their Schedule NM has some confusing language about excess generation credits that even their own billing department doesn't understand correctly. Found a $4,200 overcharge on a dental office with rooftop solar last month. The key was getting an engineer from their rates department involved instead of just customer service. They actually know how the tariffs are supposed to work.
Calvin makes a good point about getting the right people involved. KCP&L here in Kansas City has a dedicated distributed generation coordinator who actually understands their net metering tariffs. When we find billing errors, we go straight to that department instead of customer service. Cuts resolution time from months to weeks. Has anyone had success getting utilities to do prospective billing corrections, or do they typically only do backwards adjustments?
Kevin, most utilities will only do retrospective corrections in my experience. They're reluctant to admit their billing systems have ongoing errors that need prospective fixes. We usually have to threaten regulatory complaints to get them to audit their own systems going forward. Rachel, curious if you ever got resolution on that Westar case? I'm seeing more net metering billing errors as solar installations increase across our region.