Wyo. Code R. 023-0002-7
Effective Date: 09/11/2025 to Current
Rule Type: Current Rules & Regulations
Reference Number: 023.0002.7.09112025
Section 1. Authority. These rules are promulgated under the Commission's authority in Wyo. Stat. Ann. §§ 37-2-112; 37-2-204; 37-2-135.
Section 2. Applicability. Each utility serving in Wyoming not subject to Wyo. Stat. Ann. § 37-2-135 and the provisions of Sections 3 through 7 of this Chapter that files an IRP in another jurisdiction shall file that IRP with the Commission. The Commission may require any utility to file an IRP.
(a) Acknowledgment: a determination by the Commission that an IRP meets the minimum requirements of Wyo. Stat. Ann. § 37-2-135 and these Rules;
(b) Action Plan: the specific actions recommended in the IRP for at least a five-year period immediately following the filing of the IRP;
(c) Affected Electric Utility: a public electric utility other than a cooperative electric utility as defined in Wyo. Stat. Ann. § 37-17-101(a)(i);
(d) Reference Case (also referred to as business-as-usual case): an optimization modeling scenario in which all pre-established operating life assumptions of existing generation facilities are left unchanged;
(e) Sensitivity Analysis: an optimization modeling technique that considers how different values of inputs (e.g. less than expected load forecast, higher than expected natural gas prices) affect a model's output under a given resource mix assumption;
(f) Counterfactual Analysis: a form of Sensitivity Analysis wherein the Affected Electric Utility performs a model variant that considers other possible resource additions not currently included in the Preferred Portfolio, i.e., possible future resource decisions that are currently considered to be uneconomic;
(g) Preferred Portfolio: the mix of resources selected to be the least-cost, least-risk selection of resources;
(h) Near-Term Need or NTN: a subset of the Action Plan items determined necessary for the Affected Electric Utility to meet its short-term, i.e., zero to six years, load forecast.
(a) Every Affected Electric Utility shall file an IRP as directed by the Commission.
(b) The Commission may require an Affected Electric Utility to file updates to an IRP. Updates may include a detailed explanation of all changes to the Action Plan or any other information the Commission finds necessary.
(c) IRP applications under these Rules are subject to the provisions of the Wyoming Administrative Procedure Act, Wyo. Stat. Ann. § 16-3-101, et seq.
(d) The Affected Electric Utility may request the Commission waive any requirement or extend any deadline upon a showing that:
(i) compliance will impose an undue burden;
(ii) the exemption or extension is in the public interest; and
(iii) the requirement is not provided in Wyo. Stat. Ann. § 37-2-135(c)(ii).
(a) Every Affected Electric Utility shall file an initial application proposing IRP filing timelines and any specific analyses applicable to that utility. The application shall include:
(i) A proposed schedule for filing IRPs and, if applicable, updates thereto;
(ii) A request for any modifications or waivers from the requirements of these Rules; and
(iii) A request for any other procedural or substantive analysis or requirement tailored to the Affected Electric Utility's specific circumstances.
(b) Any order issued under this provision is subject to modification after notice and opportunity for a hearing upon receiving an application to amend by the Affected Electric Utility.
(a) At a minimum, IRPs shall contain:
(i) The demand and energy forecast for the Affected Electric Utility for not less than a ten-year period.
(ii) The Affected Electric Utility's options for meeting the requirements shown in its load and resource forecast in an economic and reliable manner, including:
(A) Demand-side and supply-side options; and
(B) A description and summary cost-benefit analysis of each option considered in the IRP.
(iii) The Affected Electric Utility’s assumptions and conclusions with respect to the effect of the Action Plan on the cost, adequacy, and reliability of energy service;
(b) For each Affected Electric Utility the Commission may require specific analyses, including but not limited to the following:
(i) A Reference Case based on resource operational lives established in the previously filed IRP, effective after July 1, 2024, incorporating modeling inputs with only the updated capital additions or operational service life reductions required by state or federal law;
(ii) At least one Sensitivity Analysis on the Preferred Portfolio case;
(iii) At least one Counterfactual Analysis on the Preferred Portfolio case;
(iv) A showing of the estimated cost differences between the Preferred Portfolio and the Reference Case;
(v) Reliability analyses including regional resource adequacy, power flow changes caused by retiring dispatchable resources, weather, wildfire risk and mitigation, etc . . . ;
(vi) A review and description of emerging technology resource types related to generation, storage and delivery of electricity;
(vii) A summary of how the Affected Electric Utility modeled its compliance with current regulatory requirements under state and federal law;
(viii) For any Affected Electric Utility that operates in other state jurisdictions, the Affected Electric Utility must provide a summary of the status of all interjurisdictional state allocation agreements, if any;
(ix) A detailed review of existing transmission capabilities and future needs during the Action Plan and NTN for all transmission facilities, including associated substations and terminal facilities, as applicable. The Affected Electric Utility shall generally identify the location and extent of transfer capability limitations on its transmission network related to future siting of resources;
(x) An assessment of planning reserve margins and a description of the methodology used to assess the necessary level of reliability on the system throughout the planning period;
(xi) A comparison of the electric energy and demand forecasts with existing resources and planning margin and an assessment of the need to acquire additional resources within the planning period;
(xii) An evaluation of all feasible supply and demand-side resource options on a consistent and comparable basis, taking into consideration risk and uncertainty. The evaluation shall examine the cost of each resource through its anticipated operational life; and
(xiii) An Action Plan describing the implementation plans based on the IRP analysis for the NTN, including, but not limited to:
(A) A description of the Wyoming environmental and economic externalities, including employment impacts, to the extent practicable;
(B) A Community and Employee Transition Plan to address economic externalities arising during the Action Plan period; and
(C) A plan to acquire additional resources identified in the Action Plan, including a consideration of all feasible, cost-effective supply-side and demand-side resources. The Affected Electric Utility shall describe the resources it evaluated for selection and the assumptions and methodologies used in that evaluation and any other data or analyses the Commission may require.
(a) The Affected Electric Utility shall:
(i) Provide the Commission the same access to the modeling software used by the utility to develop the IRP as the Affected Electric Utility’s employees;
(A) If the Affected Electric Utility uses a third-party to perform an IRP analysis, the Affected Electric Utility shall provide the Commission access to the software used by the third-party;
(ii) Perform any reasonable modeling runs requested by the Commission; and
(iii) Share all modeling information (e.g. solution files, input files) with the Commission upon request.
(b) The Commission may acknowledge an IRP if the Affected Electric Utility meets its burden of proof establishing that it satisfies the minimum statutory and regulatory requirements and is in the public interest;
(c) The Commission shall issue an order at the conclusion of any proceedings;
(d) Unless otherwise determined by the Commission, acknowledgement of an IRP shall not create any presumption that the present or future public convenience and necessity required or will require any resources identified in the Action Plan or NTN;
(e) An Order from the Commission acknowledging an IRP or update to an IRP does not constitute ratemaking, a determination of prudence, or pre-approval of any decision or action proposed in the IRP.