Reporting of stranded electric utility costs. Requires a cooperatively owned power supplier to submit an annual report to the utility regulatory commission (IURC) concerning the cooperatively owned power supplier's stranded costs with respect to the calendar year to which the report pertains. Defines a "cooperatively owned power supplier" as: (1) a general district corporation within the meaning of the rural electric membership corporation act (act); or (2) a nonprofit organization whose membership includes one or more corporations organized under the act. Provides that a cooperatively owned power supplier's stranded costs for a calendar year include both of the following, as applicable: (1) The difference between: (A) the forecasted costs with respect to the cooperatively owned power supplier's supply side portfolio; minus (B) the forecasted market value with respect to the cooperatively owned power supplier's supply side portfolio; for the calendar year. (2) The cooperatively owned power supplier's forecast of the amount of harm, measured as a shifting of costs among member corporations, resulting from any reduced load with respect to the calendar year. Provides that in the required report to the IURC, a cooperatively owned power supplier must provide an explanation of the reasons for any difference in amounts reported for these two elements of stranded costs. Subject to certain protections for confidential or proprietary business information, requires: (1) a cooperatively owned power supplier to: (A) make a copy of each annual report available for inspection and copying at its offices; (B) post each annual report on the cooperatively owned power supplier's Internet web site, if any; and (C) maintain each annual report in an electronic format for a period of at least five years; and (2) the IURC to post on its Internet web site each annual report received. Provides that these provisions apply to a cooperatively owned power supplier regardless of whether: (1) the cooperatively owned power supplier; or (2) any member of the cooperatively owned power supplier; has withdrawn from the jurisdiction of the IURC, as allowed under the act. Requires the IURC to adopt rules to implement these provisions.