The four coal-fired power plants of Ameren Missouri are currently planned for retirement over the 2022-2045 period, with Meramec the earliest of those at 2022.
Factors surrounding the remaining lives of the plants are in July 3 testimony that Ameren Missouri filed with the Missouri Public Service Commission in a pending rate case. Providing the bulk of the plant retirement data was Larry Loos, working as an independent contractor to Black & Veatch Corp.
Loos said the current coal plant retirement schedule estimate is:
- Meramec, 2022. The Meramec Energy Center is located at the confluence of the Meramec and Mississippi rivers near Arnold, Mo.
- Sioux, 2033. The Sioux Energy Center, which has two supercritical cyclone-fired units, is located north of the city of St. Louis on the south (west) bank of the Mississippi River.
- Labadie Units 1 and 2, 2036. The Labadie Energy Center, which has four pulverized coal subcritical power generating units, is located southwest of the city of St. Louis on the banks of the Missouri River.
- Labadie Units 3 and 4, 2042.
- Rush Island, 2045. The Rush Island Energy Center consists of two pulverized coal subcritical units located on the western bank of the Mississippi River near Festus, Mo.
The final retirement date estimates consider Ameren Missouri’s specific retirement history, Ameren Missouri’s planned capital improvements, industry accepted life span forecasts for comparable facilities, the retirement experience of plants throughout the U.S., a viable plan for timely replacement of Ameren Missouri’s retired capacity, and Ameren Missouri’s decision to retire its Meramec plant by 2022.
The combined, installed capacity of these four plants is nominally 5,650 MW, with commercial operation start dates ranging from 1953 through 1977. The primary fuel used by these plants is low-sulfur coal shipped by rail from the Powder River Basin in Wyoming.
With the exception of Labadie, each plant has a total nameplate capacity of about 1,000 MW (923 to 1,242 MW).Meramec consists of four relatively small units (137.5 to 359 MW); whereas the Sioux and Rush Island plants each consist of two relatively large units (549.7 to 621 MW). The Labadie plant consists of four relatively large units (573.7 to 621 MW).
Ameren Missouri’s planned capital expenditures, as set forth in the company’s draft integrated resource plan (IRP) documents, include the addition of scrubbers at either Labadie or Rush Island, but only if they are absolutely required, Loos noted. The addition of scrubbers (if required) at Labadie or Rush Island plant would represent extraordinary capital outlays, he added, meaning the newly-scrubbed facilities would have to run for at least another 20 years to amortize the scrubber costs.
In its reference case the company’s draft 2014 IRP reflects the timing of the addition of scrubbers to Units 3 and 4 at the Meramec Energy Center at an estimated cost $383m ($591/kW) in the 2019 to 2025 time frame. “The economics of investing nearly $400 million in generating capacity that at the time (assuming a 2022 in service date for the scrubber) will be over 60 years old is questionable at best,” Loos wrote. “Therefore, consistent with the Company’s plan, I assume that the Company will retire the Meramec Energy Center by 2022 in order to avoid this uneconomic investment.”
Loos made the assumption that if the company is required to install scrubbers, the installation will be made to Units 3 and 4 of the Labadie plant, as the company currently expects.
Gas-fired capacity is the new assumption for any coal replacement
Loos developed a timeline assuming that retired coal-fired base load generation would be replaced with gas-fired, combined-cycle generation with a 52-month planning and construction schedule and a staged approach for replacing capacity where two units are constructed at a time with no other overlap in new plant construction. To accommodate this construction timeline, he extended the estimated final retirement date of Rush Island by three years.
“My estimated retirement dates are based on the assumption that Ameren Missouri will do whatever is necessary to continue to operate the Rush Island plant beyond its estimated final retirement so as to have available adequate system capacity to provide safe and reliable electric service to its native customer base,” Loos said. “This extended operation may be as a standby, peaking, or something other than as a base load resource.”
Attached to his testimony is a detailed May 2014 report on the plants by Black & Veatch. The report noted that over the next five years, Ameren Missouri expects to spend approximately $860m on capital projects at the four plants of which only about 6% is expected to be expended at the Meramec plant, which accounts for about 16% of the company’s coal-fired generating capacity.
Notable is that a Black & Veatch report from 2009 on coal plant life expectancy assumed the utility would replace any retired coal capacity with new coal facilities. “Current market conditions however, indicate that gas-fired combined cycle generation is a far more reasonable assumption for the replacement of base load capacity for Ameren Missouri’s coal-fired plants,” the report said. “Additionally, Ameren Missouri forecasts it will not require new capacity to replace the capacity lost from its planned retirement of the Meramec Energy Center in 2022, since its capacity is not required to meet Ameren Missouri’s reserve margin.”
The report said: “Completion of the scrubbers at the Sioux Energy Center in 2010 represents the final extraordinary environmental project currently planned by the Company. Ameren Missouri has no definitive plans to install scrubbers at other plants unless required to do so.”
Founded as Union Electric in 1902, Ameren Missouri provides electric service to about 1.2 million customers across central and eastern Missouri, including the greater St. Louis area. Ameren Missouri is a unit of Ameren (NYSE: AEE), which a few months ago pulled out of non-regulated, mostly coal-fired generation in Illinois so it could focus on its regulated operations in Missouri.