REGULATORY MATTERS:	3 Months Ended
REGULATORY MATTERS:	Mar. 31, 2022
Public Utilities, Rate Matters [Abstract]
Regulatory Matters	REGULATORY MATTERS Included below is a summary of Idaho Power's most recent general rate cases and base rate changes, as well as other recent or pending notable regulatory matters and proceedings. Idaho and Oregon General Rate Cases Idaho Power's current base rates result from the Idaho Public Utilities Commission (IPUC) and Public Utility Commission of Oregon (OPUC) orders described in Note 3 - "Regulatory Matters" to the consolidated financial statements included in the 2021 Annual Report. Idaho Settlement Stipulations A May 2018 Idaho settlement stipulation related to tax reform (May 2018 Idaho Tax Reform Settlement Stipulation) is described in Note 3 - "Regulatory Matters" to the consolidated financial statements included in the 2021 Annual Report and includes provisions for the accelerated amortization of accumulated deferred investment tax credits (ADITC) to help achieve a minimum 9.4 percent Idaho-jurisdiction return on year-end equity (Idaho ROE). In addition, under the May 2018 Idaho Tax Reform Settlement Stipulation, the Idaho ROE at which Idaho Power would begin amortizing additional ADITC would revert back to 95 percent of the authorized return on equity in the next general rate case. The settlement stipulation also provides for the potential sharing between Idaho Power and Idaho customers of Idaho-jurisdictional earnings in excess of 10.0 percent of Idaho ROE. Based on its estimate of full-year 2022 Idaho ROE, in the first quarter of 2022, Idaho Power recorded no additional ADITC amortization or provision against current revenues for sharing of earnings with customers under the May 2018 Idaho Tax Reform Settlement Stipulation. Accordingly, at March 31, 2022, the full $45 million of additional ADITC remains available for future use. Idaho Power also recorded no additional ADITC amortization or provision against revenues for sharing of earnings with customers during the first quarter of 2021, based on its then-current estimate of full-year 2021 Idaho ROE. Power Cost Adjustment Mechanisms In both its Idaho and Oregon jurisdictions, Idaho Power's power cost adjustment mechanisms address the volatility of power supply costs and provide for annual adjustments to the rates charged to its retail customers. The power cost adjustment mechanisms compare Idaho Power's actual net power supply costs (primarily fuel and purchased power less wholesale energy sales) against net power supply costs being recovered in Idaho Power's retail rates. Under the power cost adjustment mechanisms, certain differences between actual net power supply costs incurred by Idaho Power and costs being recovered in retail rates are recorded as a deferred charge or credit on the balance sheet for future recovery or refund. The power supply costs deferred primarily result from changes in contracted power purchase prices and volumes, changes in wholesale market prices and transaction volumes, fuel prices, and the levels of Idaho Power's own generation. In April 2022, Idaho Power filed an application with the IPUC requesting a $103.4 million net increase in Idaho-jurisdiction power cost adjustment (PCA) revenues, effective for the 2022-2023 PCA collection period from June 1, 2022, to May 31, 2023. The net increase in PCA revenues reflects a forecasted reduction in low-cost hydroelectric generation as well as higher market energy prices and higher natural gas prices. The filing also includes $0.6 million of 2021 earnings to be shared with customers under the May 2018 Idaho Tax Reform Settlement Stipulation described above. As of the date of this report, the IPUC has not yet issued an order on the application. Idaho Fixed Cost Adjustment Mechanism The Idaho jurisdiction fixed cost adjustment (FCA) mechanism, applicable to Idaho residential and small general service customers, is designed to remove a portion of Idaho Power’s financial disincentive to invest in energy efficiency programs by separating (or decoupling) the recovery of fixed costs from the variable kilowatt-hour charge and linking it instead to a set amount per customer. Under Idaho Power's current rate design, Idaho Power recovers a portion of fixed costs through the variable kilowatt-hour charge, which may result in over-collection or under-collection of fixed costs. To return over-collection to customers or to collect under-collection from customers, the FCA mechanism allows Idaho Power to accrue, or defer, the difference between the authorized fixed-cost recovery amount per customer and the actual fixed costs per customer recovered by Idaho Power during the year. The IPUC has discretion to cap the annual increase in the FCA recovery at 3 percent of base revenue, with any excess deferred for collection in a subsequent year. In March 2022, Idaho Power filed its annual FCA update with the IPUC, requesting a decrease of $3.1 million in recovery from the FCA from $38.3 million to $35.2 million for the 2021 FCA deferral, with new rates effective for the period from June 1, 2022, to May 31, 2023. Jim Bridger Power Plant Rate Request In June 2021, Idaho Power filed an application with the IPUC requesting authorization to (a) accelerate depreciation for the Jim Bridger plant, to allow the plant to be fully depreciated and recovered by December 31, 2030, (b) establish a balancing account to track the incremental costs and benefits associated with ceasing participation in coal-fired operations at the Jim Bridger plant, and (c) adjust customer rates to recover the associated incremental annual levelized revenue requirement. In September 2021, the co-owner and operator of the Jim Bridger Plant submitted its Integrated Resource Plan (IRP) to the IPUC that contemplates ceasing coal-fired generation in units 1 and 2 in 2023 and converting those units to natural gas generation by 2024. Idaho Power's 2021 IRP included the same plan. At a public meeting in October 2021, the IPUC approved a joint motion by Idaho Power and the IPUC Staff to suspend the procedural schedule in Idaho Power's rate request case to assess new developments that impact operations at the Jim Bridger plant, citing the potential option to convert the two units to natural gas generation as well as ongoing regional haze compliance discussions. In February 2022, Idaho Power filed a request to resume the procedural schedule with an amended application to the IPUC that contemplates the conversion of units 1 and 2 to natural gas in 2024 and therefore removes from the application all investments for the portion of the plant that will be converted to support gas-fired operations, leaving just coal-related plant investments in the requested regulatory treatment. The updated filing requests authorization to adjust customer rates to recover the associated incremental annual levelized revenue requirement in the aggregate amount of $27.1 million, which included Idaho Power's share of all electric plant in service related to coal-fired operations at the Jim Bridger plant. As of the date of this report, the case remains pending at the IPUC. Wildfire Mitigation Cost Recovery In June 2021, the IPUC authorized Idaho Power to defer for future amortization incremental operations and maintenance (O&M) and depreciation expense for certain capital investments necessary to implement Idaho Power's Wildfire Mitigation Plan (WMP). The IPUC also authorized Idaho Power to record these deferred expenses as a regulatory asset until Idaho Power can request amortization of the deferred costs in a future IPUC proceeding, at which time the IPUC will have the opportunity to review actual costs and determine the amount of prudently incurred costs that Idaho Power can recover through retail rates. In the filing, Idaho Power projected spending approximately $47 million in incremental wildfire mitigation-related O&M and roughly $35 million in wildfire mitigation system-hardening capital incremental expenditures over a five-year period. The IPUC authorized a deferral period of five years, or until rates go into effect from Idaho Power's next general rate case, whichever is first. As of March 31, 2022, Idaho Power's deferral of Idaho-jurisdiction costs related to the WMP was $8.8 million.