St. Charles has shot down a developer's plans to build a massive data center, and blocked any new proposals for the next year, but Ameren has fielded at least 37 requests for similar projects seeking to plug into the local power grid.

Ameren Missouri's "economic development pipeline" lists contained 99 projects overall as of May, including 40 large manufacturing facilities interested in opening in the St. Louis region.

The potential projects could dwarf the biggest power users now in the St. Louis area — requiring many times as much electricity as Ameren's current largest customer, based on average requests.

Now, utility executives and state officials are scrambling to put new rules and rates in place to pay for and handle such "large-load" project proposals — those requesting more than

See Full Page