Working on a case where Pacific Power in Oregon has been incorrectly calculating net metering credits for a solar installation. Manufacturing facility with 2MW system has been shorted about $8K per month for the past 18 months. The utility is applying TOU rates wrong and not crediting excess generation at the proper retail rates. Has anyone seen similar issues with net metering billing? This seems like a growing problem as more commercial solar comes online.
Anyone dealt with net metering calculation errors?
Beatrice, I've seen this exact issue with NorthWestern Energy here in Montana. They were crediting solar generation at avoided cost rates instead of retail rates as required by state law. $15K recovery over two years for a small brewery with rooftop solar. The problem is most customers don't understand the complex calculations and just trust the utility got it right.
These net metering cases are becoming a specialty of mine. MLGW here in Memphis has made similar errors - they were using wrong time-of-use periods for crediting excess generation. $22K recovery for a logistics company with 500kW solar array. The key is understanding both the net metering statute and the utility's specific tariff implementation. Often they conflict and you can argue for the more favorable interpretation.
This is exactly why I've been telling clients to get independent audits of their solar billing. Puget Sound Energy here in Washington had similar issues with their Schedule 95 net metering calculations. $12K recovery for a small manufacturer because PSE was netting generation against usage hourly instead of monthly as required by tariff. These utilities need better training on renewable energy billing!