Rate and Regulatory Matters (Tables)

3 Months Ended

Mar. 31, 2024

Regulated Operations [Abstract]

Schedule of Solar Projects

The following table provides information with respect to each agreement:

	Huck Finn Solar Project(a)(b)	Boomtown Solar Project(b)(c)	Split Rail Solar Project(d)	Cass County Solar Project(c)	Vandalia Solar Project(b)(d)	Bowling Green Solar Project(b)(d)
Agreement type	Build-transfer	Build-transfer	Build-transfer	Development-transfer(e)	Self-build(f)	Self-build(f)
Facility size	200-MW	150-MW	300-MW	150-MW	50-MW	50-MW
Status of MoPSC CCN	Approved February 2023	Approved April 2023	Approved March 2024	Filed June 2023(g)	Approved March 2024	Approved March 2024
Status of FERC approval of acquisition	Received March 2023	Received October 2023	Expect to request by mid-2024	Not applicable	Not applicable	Not applicable
Earliest completion date(h)	Fourth quarter 2024	Fourth quarter 2024	Mid-2026	Fourth quarter 2024	Fourth quarter 2025	First quarter 2026

(a)The Huck Finn Solar Project is expected to support Ameren Missouri’s compliance with the state of Missouri’s renewable energy standard. Investments in the project will be eligible for recovery under the RESRAM.

(b)These projects collectively represent approximately $0.85 billion of expected capital expenditures.

(c)The Boomtown and Cass County solar projects are expected to support Ameren Missouri’s transition to renewable energy generation and serve customers under the Renewable Solutions Program.

(d)These solar projects are expected to support Ameren Missouri’s transition to renewable energy generation.

(e)Ameren Missouri entered into an agreement to acquire the Cass County Solar Project, which includes project design, land rights, and engineering, procurement, and construction agreements for a solar generation facility. Ameren Missouri will take over construction management of the Cass County facility after obtaining a CCN from the MoPSC and acquiring the project. Acquisition of the project is expected by mid-2024.

(f)Ameren Missouri entered into engineering, procurement, and construction agreements to construct these solar projects.

(g)Approval for the CCN is conditioned upon full subscription of the project capacity under the Renewable Solutions Program, a commercial, industrial, and governmental customer program. Ameren Missouri expects a decision by the MoPSC on the Cass County Solar Project CCN once this project’s capacity under the Renewable Solutions Program is fully subscribed.

(h)Expected completion dates are dependent on the timing of regulatory approvals, among other things.

Schedule of MYRP details

The following table presents the approved revenue requirements, ROE, capital structure common equity percentage, and annual rate base in the ICC’s December 2023 order, as well as the proposed revenue requirements and annual rate base amounts in the March 2024 revised MYRP:

Year	Revenue Requirement (in millions)	ROE	Capital Structure Common Equity Percentage	Annual Rate Base (in billions)
ICC’s December 2023 MYRP Order:
2024	$1,162	8.72%	50%	$3.9
2025	$1,210	8.72%	50%	$3.9
2026	$1,242	8.72%	50%	$3.9
2027	$1,255	8.72%	50%	$3.9
Ameren Illinois’ March 2024 Revised MYRP:
2024	$1,207	(a)	50%	$4.2
2025	$1,286	(a)	50%	$4.4
2026	$1,371	(a)	50%	$4.7
2027	$1,433	(a)	50%	$4.9

(a)Based on an allowed ROE of 8.72%. Ameren Illinois’ filing requests the ICC to increase the allowed ROE to 9.24%.