Kansas State University

MANHATTAN — Architectural engineering students at Kansas State University are proving they know what it takes to make a building more comfortable and energy efficient by winning the heating, ventilation and air-conditioning system selection category at ASHRAE's international design competition for the second year in a row.

Since 2005, teams from Kansas State University have received first place five times and placed second three times in the competition, which is unparalleled by any other university, according to Julia Keen and Fred Hasler, faculty advisers to the team and associate professors of architectural engineering and construction science.

This year, 39 teams from 13 countries participated in the overall competition. ASHRAE is a global society advancing human well-being through sustainable technology for the built environment.

Members of the winning Kansas State University team, all seniors in architectural engineering, include: John Gaito, Berryton; Alex Pint, Leawood; Megan Walkowiak, Lenexa; Lexi Oliver and Gordon Zimmerman, both from Overland Park; and Katie Helmer, Wichita.

For this year's competition, teams had to compare and select the best heating, ventilating and air-conditioning, or HVAC system, for a two-story building in New York City with general office space, research and development facilities, and a clean room. The teams made their selection through an analysis of the life-cycle cost, reliability, flexibility, architectural impact and maintainability of the systems, as well as the sustainability practices promoted by ASHRAE and the U.S. Green Building Council's green building, or LEED, rating system.

To prove their final selection, teams submitted a 30-page report detailing their comparison and selection process and a 15-minute video on why their recommended system was best the best choice for the building.

The Kansas State University team chose a ground source heat pump system that had the lowest life-cycle cost, highest energy efficiency, high degree of durability and redundancy, lowest architectural impact and the smallest carbon footprint.

"With this type of system, the earth is used as a heat sink to reject or absorb heat, eliminating the need for costly central plant equipment," Keen said. "In addition to the engineering analysis performed, the team presented benefits such as marketing value of the building and improved employee productivity to support the decision to select the ground source heat pump system."

Two added features of the system were proposed by the design team to increase the energy efficiency. The first was the use of vertical vegetation walls to biologically filter the indoor air to remove carbon dioxide and other volatile organic compounds.

"The result of this feature was a reduction in the quantity of required outside air and the corresponding energy to condition that air," Hasler said.

The second proposed feature was transferring waste heat generated by the braking of subway trains from a nearby subway station to heat hot water coils in the air distribution equipment serving the building. Hasler said this aided in significantly decreasing the energy required to heat the building in the winter months.