Say it’s a frosty morning. You’re downtown, hurrying along the sidewalk behind Central Library, and you notice steam curling up from the cracks—not from a manhole cover, mind you, or a storm drain or grate, but rather from fissures in the concrete. What gives?
Beneath your feet, it turns out, lies part of the “steam loop,” a network of pipes more than 15 miles long that carries pressurized steam throughout downtown. During the winter, about 71 buildings draw heat from this network: the Arch grounds, the Dome, every city-owned building, the courthouses, most big hotels.
Many of these buildings harness the steam to heat water. Busch Stadium uses it, for example, to cook the hot dogs that you devour on game day; the Tums factory, across the street, uses it to process the antacids that you may need afterward.
The city owns all the pipes, but the steam itself originates in a privately owned plant on the riverfront, just north of Laclede’s Landing. This Beaux-Arts giant of brick and stone was erected by Union Electric in 1904. It generated both steam and electricity—the same electricity that lit up the World’s Fair.
Back then, UE burned coal at the plant to produce its energy. Several ownership changes later, Ashley Energy now does the same with natural gas in what’s called a cogeneration facility. It works like this: The company burns natural gas to generate power, uses the waste heat to create steam, then taps the steam on its way out to make extra electricity. Ashley claims that the plant’s efficiency of more than 80 percent is the best you can do outside of solar or wind and has only improved since summer flooding afforded the chance to rebuild and perform a state-of-the-art upgrade.
The number of users has fallen, however, by about 45 percent in the past two decades. One reason: Many developers of loft buildings have found it more affordable, thanks to historic tax credits, to invest in their own boilers. As usership drops, though, rates rise for those who remain. So Alderman Jack Coatar of the Seventh Ward has introduced bills in recent years that would require or at least encourage all developers receiving municipal incentives, such as tax abatement, to commit to the steam loop.
None of the bills has made it out of committee.
Yet Ashley’s president, Mason Miller, expects a bill to pass sooner or later. He notes that the finalists for Amazon’s second headquarters—among them Austin, Nashville, and Toronto—have at least one common trait: some version of a steam loop.
Says Miller, “A lot of places we want to be like have embraced district energy.”
