Major discovery on a Buffalo manufacturing client - National Grid has been applying winter TOU rates year-round on their A-16 schedule since July 2020. Summer peak should be 7 AM-11 PM weekdays at $0.12847/kWh, but they've been billing winter peak (8 AM-10 PM at $0.09234/kWh) continuously. The client actually got undercharged during peak hours but massively overcharged during what should have been summer off-peak periods. Net impact is $47,000 in overcharges. Their billing system apparently never switched to summer schedule. Anyone else seeing National Grid season transition failures?
National Grid TOU Rate A-16 - Wrong Season Applied for 8 Months
Hugh - that's a significant billing error. MLGW here in Memphis had a similar issue in 2019 where their system got stuck in winter mode. The key is documenting the exact tariff language about season transitions. National Grid's A-16 should transition to summer rates on June 1st and back to winter on October 1st. If they missed the transition, every TOU customer on that schedule would be affected. This could be a class-action level problem. Have you contacted other auditors in National Grid territory?
This reminds me of Chugach Electric here in Anchorage - their system failed to transition from winter to summer TOU windows in 2019. Affected about 200 commercial accounts before someone noticed. The problem was a date format error in their billing system that interpreted "06/01" as January 6th instead of June 1st. Simple coding mistake, massive billing impact. National Grid might have the same issue.
Hugh, definitely check if this affected other A-16 customers. Entergy down here in New Orleans had a system-wide TOU error that hit 400+ accounts. One billing error usually means many more. I'd recommend pulling interval data for June, July, and August 2020 to see the rate coding. If National Grid was applying winter rates during peak summer months, the financial impact across their territory could be enormous.
Randy and Juan - great points. I've identified three other A-16 accounts with the same issue. National Grid's customer service finally admitted their billing system had a "software configuration error" that prevented proper season transitions. They're claiming it only affected accounts that were enrolled in A-16 before June 2020, but that's still hundreds of customers. They've agreed to review all A-16 accounts back to July 2020 and issue corrections. This is going to be a massive undertaking for them.
Hugh - make sure they provide detailed calculations for each correction. Don't let them just issue lump-sum credits without showing the work. MLGW tried that approach and we had to demand line-by-line recalculations to verify accuracy. Also, push for interest on the overcharges - National Grid held your client's money for 8 months due to their error. That's not the customer's fault.
This is why I always verify TOU rate applications manually for the first few months after any tariff changes. Evergy here in Kansas had billing system errors after they updated their TOU schedules in 2019. Caught it early but still took 6 months to get corrections processed. Utilities are great at implementing new rates but terrible at testing their billing systems properly.
Hugh - document everything with screenshots and save all correspondence. Rocky Mountain Power had a similar season transition failure in 2018, and when they finally processed corrections, half the calculations were wrong again. We ended up having to audit their audit. Don't assume their correction process will be error-free just because they admitted fault.
Update on this issue - APS here in Scottsdale just confirmed they had the same problem with their E-32 TOU schedule. Their system failed to transition properly in June 2020 due to COVID-related remote work disrupting their normal billing cycle monitoring. Apparently several utilities had similar issues when their billing departments were working from home and couldn't perform routine system checks. This might be more widespread than we initially thought.