Alliant Energy gave a glimpse into their new $645 million energy station on Tuesday. The natural gas facility is on the Eastern edge of Marshalltown.

Alliant says this facility is the most efficient natural gas generation station in Iowa. It's also in the top five for efficiency in the entire country.

The new plant started operation earlier this month. It replaces Alliant's older coal-fired units that were no longer cost-effective.

The facility is powerng about 500 thousand homes in Iowa.