Ameren Missouri predicts big additions of wind and natural gas to replace two coal plants it will retire during the next 20 years, and it expects to add another 10 megawatts of utility-scale solar by 2016.
The utility’s energy plans are part of a comprehensive generation plan it is required to prepare for regulators every three years. Its 2014 plan lays out the beginnings of a move away from its traditional reliance on coal power as the fuel faces ever stricter environmental regulations.
“We’re looking at retiring about a third of our coal power fleet as they reach end of life,” said Ameren spokesman Warren Wood.
The utility had already revealed it had planned to retire its Meramec power plant in south St. Louis County by 2022. Now, the utility says it will retire its Sioux plant in St. Charles County by 2033. Together, they produce about 1,800 megawatts of power.
To replace some of that capacity, Ameren plans to add 400 megawatts of wind power. The utility already has a purchase power agreement for 100 megawatts of wind from the Prairie State Wind Farm in Iowa.
The new wind generation may be developed by another party, but ultimately Ameren said it hopes to own the new wind generation.
“Over the long term we expect it would be Ameren-owned generation,” said Ajay Arora, an Ameren vice president of environmental services and generation planning.
The other big addition would come in the form of about 600 megawatts of combined cycle natural gas. Ameren’s existing gas plants are only fired up during times of peak demand in the summer months and are mostly too expensive to run other times. The new plants would use more efficient designs that can meet baseload demand using cheap gas from the ongoing shale gas boom.
In the nearer term, the utility plans to build a new 10 megawatt solar farm by 2016. Already, it is building a 5 megawatt utility-scale solar plant in O’Fallon, Mo. It hopes to have that finished by the end of the year.
Ameren doesn’t plan a big ramp up in energy efficiency. It already has efficiency programs under the state’s rules that reimburse utilities for customer efficiency programs, essentially paying them to sell less of their product.
Consumer advocates have said it’s worth it because the savings offset the higher rates.
Ameren plans to keep its efficiency program expenditures constant, spending $148 million from 2016 through 2018, compared with $147 million from 2013 through 2015.