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Iowa’s First Net-Zero Building

Century-old property will use a PV array, geothermal, and a green roof


Century-old property will use a PV array, geothermal, and a green roof.

This century-old building will achieve net-zero energy using a PV array, geothermal heating and cooling, and a green roof. PHOTO COURTESY OF MODUS ENGINEERING

The Hawkeye State is ready to launch its first net-zero commercial project – the 100-year-old Market 1 building in Des Moines.

A project spearheaded by Modus Engineering, a firm specializing in sustainable and high performance buildings, Market 1 posed a series of difficult challenges. When the 50,000-square-foot building was constructed in 1909, on-site coal storage and a boiler determined its energy consumption.

With a $15 million investment, the completed Market 1 will feature one of the largest PV arrays in the Midwest, geothermal heating and cooling, rooftop gardens, and design elements to create a building that is aesthetically pleasing and highly efficient while maintaining its historical character.

The net-zero energy status means that the property will produce all of its own energy needs and any excess production can be sold back to the grid and paid by the utility company.

“We are at a time and a place where technology and desire are crossing paths,” says Modus Engineering partner Harry Doyle. “We’ve long wanted to do things like create energy-producing buildings, but the technology was an obstacle. Now it is our ally.”