DATA from our energy centers

Providing safe, reliable, cleaner and affordable energy takes a number of resources. Each has an environmental footprint, and many carry additional costs. Ameren works with customers, shareholders, policymakers and environmental groups to find smart solutions. Our values, which include accountability, integrity and stewardship, help form our policies now and in the future.

Click on a generation source below for more information about our energy centers.
  • Coal-Fired
  • Landfill Gas
  • Nuclear
  • Renewable Power Purchases
  • Hydroelectric
  • Natural Gas-Fired
  • Oil-Fired
  • Solar


Select an icon on the map to map learn more details about the energy centers.


Select an icon on the map to map learn more details about the energy centers.

Landfill Gas

Maryland Heights Renewable Energy Center

  • Location: Maryland Heights, Mo.
  • Capability: 8 MW*
  • Began Operation: 2012
  • Generation: 39,306 net megawatt-hours 2017
Air Quality and Greenhouse Gases

2017 emissions**:

  • SO2: 0.4 short ton
  • NOx: 5.1 short tons
  • CO2: 32,040 short tons

Added to Ameren Missouri’s fleet in 2012, this renewable energy center captures an otherwise untapped resource—methane gas from a landfill—and uses it to create clean, reliable electricity.

This facility removes the siloxane, hydrogen sulfides and other non-hydrocarbons prior to combustion. Additionally, energy center equipment compresses and removes moisture from the previously wasted methane from decomposing trash at the adjacent Maryland Heights landfill.

*Source: Ameren Corporation (2018). 2017 Form 10-K.
**Emissions are based on emission factors and unit operations for calendar year 2017.


Callaway Energy Center

  • Location: Callaway County, Mo.
  • Capability: 1,194 MW*
  • Began Operation: 1984
  • Watershed: Missouri River
  • Cooling Type: Natural draft tower
Water Usage
  • Withdrawn: Approximately 7,907 million gallons 2017
  • Recycle: 146 million gallons, 2017
  • Estimated consumption: 5,793 million gallons 2017
  • Generation: 8,304,127 net megawatt-hours, 2017
  • Water consumed: 698 gallons per MWh generated, 2017
  • Temperature rise**: Negligible

Ameren Missouri has sufficient installed spent fuel storage capacity at Callaway Energy Center until 2044.*** This capacity includes wet pool storage within the Energy Center, as well as the recently completed dry cask storage system built next to the Energy Center. This level of storage capacity will be sufficient for the licensed life of the Energy Center.

*Source: Ameren Corporation (2018). 2017 Form 10-K.
**Thermal effects from the discharge of cooling water are insignificant, as most of the heat is dissipated by evaporation through the natural draft cooling tower.
***License extended through 2044 by the Nuclear Regulatory Commissions in March 2015.

Renewable Power Purchases

Combined, Ameren Illinois and Ameren Missouri purchase approximately 900,000 megawatt-hours (MWh) per year of wind and solar power. That’s about the same amount of energy annually used by approximately 69,000 average homes.

While we do not own or operate these generation facilities, our purchase agreements help support renewable power in the Midwest.

Represented on the map are the locations of generation facilities. Below are the company names, type of power and annual quantity commitments of our long-term purchase agreements.

Ameren Illinois Long-Term Agreements

Start Date: June 1, 2012 End Date: May 31, 2032

600,000 annual MWh total from the following facilities:

  • MidAmerican Wind
  • Rockford Solar, Solar
  • Iberdrola Renewables, Wind
  • EDP Renewables, Wind
Ameren Illinois Utility Scale Wind and Solar 15-Year Agreement

Start Date: May be as early as June 1, 2019. Runs 15 years from start date of facility.

In excess of 300,000 annual MWh total from the following facilities:

  • Cardinal Point LLC
  • Prairie State Solar, LLC
  • Broadlands Wind Farm
Ameren Missouri Long-Term Agreements

Start Date: Sept. 1, 2009 End Date: Aug. 31, 2024

  • EDP Renewables (f/k/a Horizon Wind Energy), Wind, 301,000 annual MWh

Below are the type of power and quantity commitments for our short-term renewable energy credits (RECs).

Ameren Illinois purchases RECs from various suppliers. The plan year is June 1 through May 31 of the following year. A REC is created for each megawatt-hour of renewable electricity generated and delivered to power the grid.

Ameren Illinois Short-Term Agreements
  • 2017-2018 Plan Year: Total of 255,785 Renewable Energy Credits (RECs)*
    • 251,767 Wind RECs
    • 2,626 Solar RECs
Ameren Illinois Distributed Generation Agreements
  • 2017-2018 Plan Year: 3,003 Solar MWh
  • 2018-2019 Plan Year: 5,918 Solar MWh
  • 2019-2020 Plan Year: 5,918 Solar MWh
  • 2020-2021 Plan Year: 4,964 Solar MWh
  • 2021-2022 Plan Year: 4,529 Solar MWh
  • 2022-2023 Plan Year: 2,915 Solar MWh

Natural Gas-Fired

Ameren Missouri operates a fleet of nine natural gas-fired energy centers in Missouri and Illinois. These energy centers each produce a comparatively low level of emissions. Below are total fleetwide emissions and generation information.

Meramec Energy Center

  • Location: St. Louis County, Mo.
  • Capability: 236 MW* (Units 1&2)
  • Began Operation: 1953
  • Watershed: Mississippi/Meramec Rivers
  • Cooling Type: Once-through (returns most of the water withdrawn to the source, consuming a fraction of water withdrawn)
Air Quality and Greenhouse Gases

Units 1&2: Began the exclusive use of natural gas to produce energy in April 2016.

Pollution control equipment: Electrostatic precipitators

Units 1&2 2017 emissions**:

  • SO2: 1 short ton
  • NOx: 7 short tons
  • CO2: 12,874 short tons
  • Mercury: 0 lbs

Combustion Turbine Generators (CTG) Fleet Information

  • Total units: 37***
  • Total capability: 2,602 MW****
  • Total generation: 287,040 net megawatt-hours 2017
Air Quality and Greenhouse Gases

2017 emissions:

  • SO2: 1 short ton*****
  • NOx: 104 short tons*****
  • CO2: 195,441 short tons
  • Mercury: 0 lb

*Source: Ameren Corporation (2018). 2017 Form 10-K.
**Emissions are based on measurements by the continuous emission monitoring systems for calendar year 2017.
***Some of these units have “dual-fuel” capability, meaning they can utilize fuel oil as backup for combustion.
****Source: Ameren Corporation (2018). 2017 Form 10-K. This total does not include Meramec Energy Center Units 1&2 (236 MW natural-gas-fueled).
*****Reported emissions to USEPA.


Ameren Missouri operates a fleet of oil-fired combustion turbine generators (CTGs) in Missouri and Illinois. Compared with coal-fired plants, these energy centers each produce a comparatively low level of emissions. Below are total fleet-wide emissions and generation information.

Fleet Information
  • Total units: 5
  • Total capability: 272 MW*
  • Total generation: 0 net megawatt-hours 2017**
Air Quality and Greenhouse Gases

2017 emissions:

  • SO2: 4 short tons***
  • NOx: 11 short tons***
  • CO2: 3,495 short tons
  • Mercury: 0 lb

*Source: Ameren Corporation (2018). 2017 Form 10-K.
**Units operated but there was zero net-generation.
***Reported emissions to USEPA.


O’Fallon Renewable Energy Center

  • Location: O'Fallon, Mo.
  • Capability: 3 MW*
  • Began Operation: 2014
  • Number of solar panels: More than 19,000

This facility is one of Ameren Missouri's investments on behalf of customers for cleaner air and renewable energy. Groundbreaking on the 19-acre facility in O'Fallon took place in April 2014 and created almost 70 construction jobs.

  • Generation: 5,994 net megawatt-hours, 2017

*Source: Ameren Corporation (2018). 2017 Form 10-K.