Minnesota electric and gas customers were temporarily overcharged on interim rates in nine out of 10 cases since 2008. Interim rates are granted almost automatically to utilities during the months a rate increase request is under regulatory review. Any overcharges are refunded with interest after final rates are approved.
Note: Dollars in millions InterimApprovedPercent
CompanyYearincreaseincreaserefunded
Minnesota Power (E)2008$36.4$15.258%
Xcel Energy (E)2008$150.5$103.931%
CenterPoint Energy (G)2008$77.2$61.520%
Minn. Energy Resources (G)2008$26.2$20.821%
Xcel Energy (G)2009$14.4$9.534%
Minnesota Power* (E)2009$32.8$36.1-10%
Otter Tail Power Co. (E)2010$6.3$2.462%
Interstate Power Co. (E)2010$17.7$14.121%
Xcel Energy (E)2010$153.7$76.850%
Minn. Energy Resources (G)2010$9.8$7.8021%
Note: (E) electric rates; (G) gas rates
*Interim rate decision on appeal before Minnesota Supreme Court.
Source: Minnesota attorney general