Regulators in Minnesota and Pennsylvania have approved electric service tariffs with real-time pricing (RTP). In Minnesota, the PUC directed Otter Tail Power Co. to offer large-volume customers: 1) a customer-specific baseline load priced at a standard rate, with deviations priced hourly at the spot market, reflecting a profit margin plus marginal operating and outage costs; and 2) a simplified offer that eliminates the baseline calculation, increases fixed charges, and bills all energy use at the real-time incremental rate. (The incremental "outage charge" contained in both offerings reflects high costs during hours when the reliability of the system could be eroded by increased or decreased consumption.) Re Otter Tail Pwr. Co., Docket No. E-017/M-95-1044, March 18, 1996 (Minn.P.U.C.).