The runners-up could still get a hefty consolation prize. The Energy Department said it will also issue a "follow-on solicitation" seeking further modular reactor projects.
Officials with Pittsburgh-based Westinghouse Electric Co. and Ameren said they plan to pursue federal support in the project's second phase.
"Our alliance and the entire state of Missouri stand ready to capitalize on this important project that will also help create a cleaner energy portfolio for our state and our country," said Warner Baxter, president and chief executive officer of Ameren Missouri.
Just three weeks ago, Westinghouse and Ameren hosted a small modular reactor "supplier summit" at the Callaway nuclear plant near Fulton for 300 industry representatives, from heavy equipment operators to trade unions and design engineers.
Not everyone in Missouri was bemoaning the loss of a federal investment that could approach nearly half a billion dollars.
"If (small modular reactors were a good investment then Ameren Missouri should have no problem raising private capital to finance a nuclear reactor instead of looking to taxpayers and ratepayers," said Ed Smith, safe energy director for the Missouri Coalition for the Environment, which opposed the project.
"Nuclear power has been too risky for Wall Street for decades, is too risky for insurance companies to insure, and there is still no solution for storing radioactive waste," he said, "which remains a health threat for millions of years beyond its useful life in energy creation."
Alan Scher Zagier can be reached at http://twitter.com/azagier