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Ameren Missouri outlines least-cost approach to reliably meet customer energy needs in an environmentally responsible manner

ST. LOUIS, Sept. 26, 2023 /PRNewswire/ -- Today Ameren Missouri, a subsidiary of Ameren Corporation (NYSE: AEE), announced its updated 20-year plan to provide reliable, affordable and resilient energy to its customers. The plan calls for investment in new on-demand energy sources to ensure the long-term stability of the energy grid and accelerated deployment of renewable energy generation. The Company's plan is environmentally responsible and consistent with its sustainability goals.


Ameren Missouri's Integrated Resource Plan (IRP) is designed to meet the projected energy needs of its customers in an increasingly electrified future. It includes a balanced mix of energy sources to support continued reliability even under extreme weather conditions.

"Thoughtfully integrating a new, diverse mix of generation sources while maintaining the availability of our existing energy centers through retirement is essential for a reliable, resilient and affordable clean energy future," said Mark Birk, chairman and president of Ameren Missouri. "By making smart investments in an environmentally responsible way, we're strengthening the energy grid without compromising on affordability."

Highlights of the 2023 IRP include:

  • Deploying an 800-megawatt (MW) on-demand, natural gas simple-cycle energy center by 2027, representing a potential investment of $800 million, to provide backup power at times of peak winter and summer energy demand.
  • Moving back the previously announced addition of a combined-cycle energy center to 2033. This 1,200-MW facility is now scheduled to go in service following the retirement of the Sioux Energy Center in 2032.
  • Accelerating Ameren Missouri's planned renewable energy additions by four years. The company plans to add 4,700 MW of new renewable energy by 2036. This represents a total potential investment of approximately $9.5 billion. The company maintains its goal of 2,800 MW by 2030.
  • Adding 800 MW of battery storage, including 400 MW by 2030 – five years earlier than previously planned – with an additional 400 MW of battery storage by 2035. This represents a total potential investment of $1.3 billion through 2035.
  • Planning 1,200 MW of clean, on-demand generation to be ready to serve customers in 2040 and an additional 1,200 MW by 2043.

"Our strategic investments are timed to keep rates as low as possible for our customers while making efficient system upgrades to provide clean, reliable and affordable energy for the long-term," said Ajay Arora, senior vice president and chief renewable development officer at Ameren Missouri.

Since last updating Ameren Missouri's long-term plans in June 2022, the company has:

  • Retired the coal-fired Meramec Energy Center at the end of 2022.
  • Proposed a 2024 retirement of the coal-fired Rush Island Energy Center based on the projected completion date of grid reliability updates. The ultimate retirement date is subject to approval by the U.S. District Court for the Eastern District of Missouri.
  • Received approval to acquire, upon projected completion next year, two solar facilities with combined capacity of 350 MW.
  • Announced plans to acquire or build an additional 550 MW of solar capacity targeted to be ready to serve customers between next year and 2026.

Customers will continue to have the ability to manage their electric bills through robust, cost-effective energy efficiency and demand response programs. Between 2020 and 2022, these programs have saved more than 930,000 megawatt-hours of energy. That's equivalent to the energy used by nearly 76,000 average residential homes in a year.


Ameren's companywide goal of net-zero carbon emissions by 2045 is science based and consistent with the objectives of the Paris Agreement and limiting global temperature rise to 1.5 degrees Celsius. This goal encompasses both Scope 1 and Scope 2 emissions, including other greenhouse gas emissions of methane, nitrous oxide and sulfur hexafluoride. This goal is dependent on a variety of factors, including cost-effective advancements in innovative clean energy technologies as well as constructive federal and state energy and economic policies. Interim targets include reducing carbon emissions 60% by 2030 and 85% by 2040, in each case based on 2005 levels.

Additional details about Ameren Missouri's plans to accelerate investments in long-term reliability for Missourians are available at AmerenMissouri.com/Reliable.

About Ameren Missouri
Ameren Missouri has been providing electric and gas service for more than 100 years. Ameren Missouri's mission is to power the quality of life for its 1.2 million electric and 135,000 natural gas customers in central and eastern Missouri. The company's service area covers 64 counties and more than 500 communities, including the greater St. Louis area. For more information, visit Ameren.com/Missouri or follow us on Twitter at @AmerenMissouri or Facebook.com/AmerenMissouri.

Forward-looking Statements
Statements in this release not based on historical facts are considered "forward-looking" and, accordingly, involve risks and uncertainties that could cause actual results to differ materially from those discussed. Although such forward-looking statements have been made in good faith and are based on reasonable assumptions, there is no assurance that the expected results will be achieved. These statements include (without limitation) statements as to future expectations, beliefs, plans, projections, strategies, targets, estimates, objectives, events, conditions, and financial performance. In connection with the "safe harbor" provisions of the Private Securities Litigation Reform Act of 1995, Ameren and Ameren Missouri are providing this cautionary statement to identify important factors that could cause actual results to differ materially from those anticipated. The following factors, in addition to those discussed under Risk Factors in Ameren's and Ameren Missouri's Annual Report on Form 10-K for the year ended December 31, 2022, and elsewhere in this release and in our other filings with the Securities and Exchange Commission, could cause actual results to differ materially from management expectations suggested in such forward-looking statements:

  • regulatory, judicial, or legislative actions, and any changes in regulatory policies and ratemaking determinations, that may change regulatory recovery mechanisms, such as those that may result from the impact of a final ruling to be issued by the United States District Court for the Eastern District of Missouri regarding its September 2019 remedy order for the Rush Island Energy Center and the Missouri Public Service Commission ("MoPSC") staff review of the planned Rush Island Energy Center retirement;
  • our ability to control costs and make substantial investments in our businesses, including our ability to recover costs and investments, and to earn our allowed returns on equity, within frameworks established by our regulators, while maintaining affordability of our services for our customers;
  • the effect on Ameren Missouri of any customer rate caps or limitations on increasing the electric service revenue requirement pursuant to Ameren Missouri's election to use the plant-in-service accounting;
  • Ameren Missouri's ability to construct and/or acquire wind, solar, and other renewable energy generation facilities and battery storage, as well as natural gas-fired combined cycle energy centers, retire fossil fuel-fired energy centers, and implement new or existing customer energy-efficiency programs, including any such construction, acquisition, retirement, or implementation in connection with its Smart Energy Plan, integrated resource plan, or emissions reduction goals, and to recover its cost of investment, a related return, and, in the case of customer energy-efficiency programs, any lost margins in a timely manner, each of which is affected by the ability to obtain all necessary regulatory and project approvals, including certificates of convenience and necessity from the MoPSC or any other required approvals for the addition of renewable resources;
  • Ameren Missouri's ability to use or transfer federal production and investment tax credits related to renewable energy projects; the cost of wind, solar, and other renewable generation and storage technologies; and our ability to obtain timely interconnection agreements with the Midcontinent Independent System Operator, Inc., a regional transmission organization ("MISO") or other regional transmission organizations at an acceptable cost for each facility;
  • the success of competitive bids related to requests for proposals associated with the MISO's long-range transmission planning;
  • the inability of our counterparties to meet their obligations with respect to contracts, credit agreements, and financial instruments, including as they relate to the construction and acquisition of electric and natural gas utility infrastructure and the ability of counterparties to complete projects, which is dependent upon the availability of necessary materials and equipment, including those obligations that are affected by supply chain disruptions;
  • advancements in energy technologies, including carbon capture, utilization, and sequestration, hydrogen fuel for electric production and energy storage, next generation nuclear, large-scale long-cycle battery energy storage, and the impact of federal and state energy and economic policies with respect to those technologies;
  • the effects of changes in federal, state, or local laws and other governmental actions, including monetary, fiscal, foreign trade, and energy policies;
  • the effects of changes in federal, state, or local tax laws or rates, including the effects of the Inflation Reduction Act of 2022 ("IRA") and the 15% minimum tax on adjusted financial statement income, as well as additional regulations, interpretations, amendments, or technical corrections to or in connection with the IRA, and challenges, if any, to the tax positions taken by us, as well as resulting effects on customer rates and the recoverability of the minimum tax imposed under the IRA;
  • the effects on energy prices and demand for our services resulting from technological advances, including advances in customer energy efficiency, electric vehicles, electrification of various industries, energy storage, and private generation sources, which generate electricity at the site of consumption and are becoming more cost-competitive;
  • the cost and availability of fuel, such as low-sulfur coal, natural gas, and enriched uranium used to produce electricity; the cost and availability of natural gas for distribution and purchased power, including capacity, zero emission credits, renewable energy credits, and emission allowances; and the level and volatility of future market prices for such commodities and credits;
  • disruptions in the delivery of fuel, failure of our fuel suppliers to provide adequate quantities or quality of fuel, or lack of adequate inventories of fuel, including nuclear fuel assemblies from the one Nuclear Regulatory Commission-licensed supplier of Ameren Missouri's Callaway Energy Center assemblies;
  • the cost and availability of transmission capacity for the energy generated by Ameren Missouri's energy centers or required to satisfy our energy sales;
  • the effectiveness of our risk management strategies and our use of financial and derivative instruments;
  • the ability to obtain sufficient insurance, or, in the absence of insurance, the ability to timely recover uninsured losses from our customers;
  • the impact of cyberattacks and data security risks on us or our suppliers, which could, among other things, result in the loss of operational control of energy centers and electric and natural gas transmission and distribution systems and/or the loss of data, such as customer, employee, financial, and operating system information;
  • acts of sabotage, which have increased in frequency and severity within the utility industry, war, terrorism, or other intentionally disruptive acts;
  • business, economic, and capital market conditions, including the impact of such conditions on interest rates, inflation, and investments;
  • the impact of inflation or a recession on our customers and the related impact on our results of operations, financial position, and liquidity;
  • disruptions of the capital and credit markets, deterioration in our credit metrics, or other events that may have an adverse effect on the cost or availability of capital, including short-term credit and liquidity, and our ability to access the capital and credit markets on reasonable terms when needed;
  • the actions of credit rating agencies and the effects of such actions;
  • the impact of weather conditions and other natural phenomena on us and our customers, including the impact of system outages and the level of wind and solar resources;
  • the construction, installation, performance, and cost recovery of generation, transmission, and distribution assets;
  • the ability to maintain system reliability during the transition to clean energy generation by Ameren Missouri and the electric utility industry, including within the MISO, as well as Ameren Missouri's ability to meet generation capacity obligations;
  • the effects of failures of electric generation, electric and natural gas transmission or distribution, or natural gas storage facilities systems and equipment, which could result in unanticipated liabilities or unplanned outages;
  • the operation of Ameren Missouri's Callaway Energy Center, including planned and unplanned outages, as well as the ability to recover costs associated with such outages and the impact of such outages on off-system sales and purchased power, among other things;
  • Ameren Missouri's ability to recover the remaining investment and decommissioning costs associated with the retirement of an energy center, as well as the ability to earn a return on that remaining investment and those decommissioning costs;
  • the impact of current environmental laws and new, more stringent, or changing requirements, including those related to New Source Review provisions of the Clean Air Act, carbon dioxide, nitrogen oxides, and other emissions and discharges, Illinois emission standards, cooling water intake structures, coal combustion residuals, energy efficiency, and wildlife protection, that could limit or terminate the operation of certain of Ameren Missouri's energy centers, increase our operating costs or investment requirements, result in an impairment of our assets, cause us to sell our assets, reduce our customers' demand for electricity or natural gas, or otherwise have a negative financial effect;
  • the impact of complying with renewable energy standards in Missouri;
  • the effectiveness of Ameren Missouri's customer energy-efficiency programs and the related revenues and performance incentives earned under its Missouri Energy Efficiency Investment Act programs;
  • labor disputes, work force reductions, changes in future wage and employee benefits costs, including those resulting from changes in discount rates, mortality tables, returns on benefit plan assets, and other assumptions;
  • the impact of negative opinions of us or our utility services that our customers, investors, legislators, regulators, creditors, or other stakeholders may have or develop, which could result from a variety of factors, including failures in system reliability, failure to implement our investment plans or to protect sensitive customer information, increases in rates, negative media coverage, or concerns about environmental, social, and/or governance practices;
  • the impact of adopting new accounting guidance;
  • the effects of strategic initiatives, including mergers, acquisitions, and divestitures;
  • legal and administrative proceedings;
  • pandemics or other health events, and their impacts on our results of operations, financial position, and liquidity; and
  • the impacts of the Russian invasion of Ukraine, related sanctions imposed by the U.S. and other governments, and any broadening of the conflict, including potential impacts on the cost and availability of fuel, natural gas, enriched uranium, and other commodities, materials, and services, the inability of our counterparties to perform their obligations, disruptions in the capital and credit markets, and other impacts on business, economic, and geopolitical conditions, including inflation.

New factors emerge from time to time, and it is not possible for us to predict all of such factors, nor can we assess the impact of each such factor on the business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained or implied in any forward-looking statement. Given these uncertainties, undue reliance should not be placed on these forward-looking statements. Except to the extent required by the federal securities laws, Ameren and Ameren Missouri undertake no obligation to update or revise publicly any forward-looking statements to reflect new information or future events.

SOURCE Ameren Missouri

For further information: CONTACTS: Media: Ameren Communications, 314.554.2182, communications@ameren.com; Investors: Andrew Kirk, 314.554.3942, akirk@ameren.com