HVAC Designs

In Minnesota’s climate, heating, ventilation, and air conditioning (HVAC) usually represent 30 to 40 percent of the total energy costs for commercial buildings. While costs to heat water, keep the lights on, and run data centers are significant, climate control trumps all other expenditures. The amount spent on HVAC can creep even higher if the building has special HVAC needs—for example, the stringent requirements of a health care building or a laboratory.

At the same time, there is a growing awareness of a need for careful and sustainable energy use, and fuel costs are high. So the HVAC choices that businesses make when building or renovating are important to their future profitability and well-being.

Traditionally, companies have expected HVAC systems to pay for themselves relatively quickly, says Steve Wernersbach, an engineer at Minneapolis architecture, engineering, and construction firm Ellerbe Becket. But that’s beginning to change. “In the old days, there was a three-year life cycle cost on it,” Wernersbach says. “If it didn’t pay back within three years, owners didn’t want to do it. Now, though, with LEED [Leadership in Energy and Environmental Design, a building certification system developed by the U.S. Green Building Council] and the concern for sustainability, that is changing. We’re seeing clients that are more open to longer payback periods.”

Some organizations are more likely to consider long paybacks than others. Doug Lucht, senior mechanical engineer at Sebesta Blomberg, an engineering and construction support firm headquartered in Roseville, does most of his work for the University of Minnesota. He says that the university is willing to consider projects that take up to seven to 10 years to pay for themselves. But even developers and corporate clients are taking a longer view.

“One of the biggest changes we’ve seen isn’t necessarily equipment based, but it’s the attitude of the owners,” Lucht says. “We’ve definitely seen a change in how the owners perceive energy-efficient design. It used to be that [engineers] didn’t necessarily bring so many things to the table, because you knew if it didn’t pay for itself quickly, it just wouldn’t go forward. But now it’s more of a collaborative effort, because you’ve got the owner and the engineer working toward the same goal. And that’s refreshing.”

But let’s be realistic, says Leighton Deer, an engineer at HGA Architects and Engineers in Minneapolis: The decision process is still centered on “cost, cost, and a little bit more on cost.” At the proposal stage, the engineer is explaining why energy efficiency should be pursued and valued. Most owners would rather put their money into their business itself, not into infrastructure.

That’s why it’s a good thing engineers now have new, more sophisticated tools to design HVAC systems with less waste, greater comfort, and less impact on the planet.