Ameren Missouri gas additions form the backbone of a major generation construction program through 2045. The utility filed its 2026 Integrated Resource Plan with Missouri regulators on September 28. The 20-year roadmap responds to rising electricity demand, especially from data centers and other large customers. It proposes 10.6 GW of new natural gas resources alongside solar, wind, storage and nuclear capacity.
The plan comes as Ameren Missouri expects electricity sales to grow by 5% to 6% annually. Large-load deliveries could also increase sharply during the planning period. However, the $31.8 billion figure represents Ameren’s broader projected 2026-2030 capital program. It does not represent the cost of the 10.6 GW gas buildout alone.
Ameren Missouri gas additions target rising demand
The construction program includes several types of natural gas generation. Combined-cycle plants will provide much of the planned around-the-clock capacity.
Ameren Missouri plans 2,100 MW of combined-cycle generation by 2031. It then expects another 2,800 MW by 2035. A further 1,400 MW could enter service by 2042.
The utility also plans 1,900 MW of simple-cycle gas generation by 2029. Another 2,400 MW could follow after 2040. These units would provide flexible generation during periods of high electricity demand.
In addition, the plan includes 500 MW of natural gas fuel cells by 2030. Ameren describes the technology as scalable and capable of delivering on-demand electricity.
The gas program reflects changing electricity demand across Missouri. Ameren expects large-load deliveries to rise significantly between 2027 and 2046.
The utility has committed to serving 2.8 GW of aggregate large-load demand by 2030. That figure nearly doubles its 1.5 GW expectation from 2025.
New York is also committing billions to reshape its power infrastructure, with a $26 billion green energy initiative supporting new clean-energy construction and grid investment. The development underscores the scale of US electricity infrastructure spending as utilities prepare for rising demand.
Ameren Missouri gas additions reshape the generation mix
The construction strategy does not rely exclusively on gas generation. Instead, Ameren plans to add 3.6 GW of solar capacity, 1.5 GW of wind and 2.4 GW of storage.
The solar program includes 1,300 MW by 2030. Another 2,300 MW would follow by 2045. The company also plans 1,500 MW of wind resources after 2030.
Meanwhile, the plan includes 1,200 MW of new nuclear generation by 2040. Ameren has not selected the technology or location for that capacity.
The utility is considering advanced large-scale reactors and small modular reactors. It also expects to seek an operating license extension for the Callaway nuclear plant beyond 2044.
The strategy also changes Missouri’s coal generation portfolio. Ameren plans to retire the Sioux Energy Center by 2035. It expects to retire all four Labadie Energy Center units by 2042.
The Missouri Public Service Commission will review the non-binding resource plan. Ameren files its integrated resource plan with the commission every three years.
The latest filing follows earlier planning that projected significant generation and infrastructure investment. Ameren’s wider 2026-2030 capital expenditure outlook reaches $31.8 billion at the midpoint. Ameren Missouri represents a major share of that investment.
However, the new generation projects still require regulatory approvals and detailed development decisions. The IRP therefore establishes a long-term construction pathway rather than final approval for every facility.
Project Fact Sheet
Project: Ameren Missouri 2026 Integrated Resource Plan.
Location: Ameren Missouri service territory, Missouri, United States.
Planning period: 2026-2045.
Status: Filed with the Missouri Public Service Commission on September 28, 2026.
Project type: Long-term electricity generation and grid resource construction program.
Natural gas capacity: 10.6 GW of planned additions.
Combined-cycle gas: 2,100 MW by 2031, 2,800 MW by 2035 and 1,400 MW by 2042.
Simple-cycle gas: 1,900 MW by 2029 and 2,400 MW after 2040.
Gas fuel cells: 500 MW by 2030.
Solar capacity: 3.6 GW through 2045.
Wind capacity: 1.5 GW after 2030.
Battery storage: 2.4 GW by 2030.
New nuclear capacity: 1.2 GW by 2040.
Coal retirements: Sioux by 2035 and Labadie by 2042.
Wider capital context: Ameren projects $31.8 billion of capital spending across 2026-2030.
Demand outlook: Up to 9 GW of growth under high-load scenarios by 2045.
Project Team
Owner and utility: Ameren Missouri
Parent company: Ameren Corporation
Regulator: Missouri Public Service Commission
Grid planning environment: Midcontinent Independent System Operator
Large-load customers: Data centers and other major electricity users
Generation developers/EPC contractors: Not yet identified for most planned facilities.
Nuclear technology suppliers: Not selected; Ameren is considering advanced large-scale reactors and small modular reactors.
Leave a Reply