(2)(a) The commission shall provide parties to the proceeding with the procedural rights described in ORS 756.500 to 756.610, including the opportunity to develop an evidentiary record, conduct discovery, introduce evidence, conduct cross-examination and submit written briefs and oral arguments.
(b) The petitioner shall have the burden of showing, by a preponderance of the evidence, that the investment or cost contributes to compliance with ORS 469A.400 to 469A.475.
(c) The commission shall issue a written order with findings on the evidentiary record development in the proceeding.
(d) Except as provided under ORS 756.610, a determination by the commission that an investment or cost contributes to compliance with ORS 469A.400 to 469A.475 is final and may not be reexamined.
(3) Upon determining that an investment or cost of an electric company contributes to compliance with ORS 469A.400 to 469A.475, the commission shall determine the actual or anticipated rate impact for the investment or cost on the same basis and with the same treatment for similarly situated investments or costs in the most recently approved general rate case or other relevant rate making proceeding. The commission shall use the actual or anticipated rate impact of each investment or cost to calculate the cumulative rate impact and shall:
(a) Cumulatively calculate the rate impact caused by all investments or costs that have been the subject of a proceeding pursuant to this section, and must be included in calculation for the time period that the investment or cost would affect rates, as adjusted by any change in net costs expected or foreseeable at the time of inclusion;
(b) Make any adjustments to the cumulative rate impact if the initial rate treatment was calculated on the basis of forecasted rate impact;
(c) Allow parties to the proceeding to propose alternative rate or accounting treatment of the investment or cost to limit the potential rate impact of the investment or cost; and
(d) Utilize cost allocation methodologies for attributing rate impacts of investments or costs for multistate electric companies.
(4) Upon a determination that the actual or anticipated cumulative rate impact calculated under subsection (3) of this section exceeds six percent of the annual revenue requirement for a year, the commission shall provide an exemption from further compliance with the requirements of ORS 469A.400 to 469A.475. An exemption must be:
(a) Narrowly tailored to otherwise give full force and effect to the requirements of ORS 469A.400 to 469A.475 that can be complied with without regard to the cumulative rate impact; and
(b) Limited in duration to only such time as is necessary to allow for additional investments and actual or forecasted costs to be made or incurred without exceeding the cumulative rate impact.
(5) A determination by the commission made under this section shall have no effect on and may not be used as collateral or presumptive evidence in any other proceeding that determines rate recovery of the investment or cost, including in a general rate case or in a proceeding under ORS 469A.120.
(6) The commission may, on its own motion pursuant to ORS 756.515, open a proceeding under this section and direct an electric company to make a filing described under subsection (1) of this section. [2021 c.508 §10]