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A sustainable yet practical approach to development of a new agriculture complex at Chemeketa Community College has produced a building expected to have net-zero energy use.

The anchor of the northern edge of an 8-acre campus in Salem is the 15,000-square-foot classroom building. FFA Architecture + Interiors designed the building, Lango Hansen Landscape Architects oversaw the exterior landscaping, and Swinerton Builders completed construction recently.

The project team had high sustainability goals. A mass-plywood-panel structure was chosen, along with a natural air ventilation system, and photovoltaic panels. Chemeketa Community College and FFA worked with Energy Trust of Oregon to help offset costs via the nonprofit’s Path to Net Zero program.

FFA Associate Partner Edward Running said when he starts work on a new project, he first sees what financial resources are available.

鈥淭he inability to make (a) better building has been cost,鈥� he said.

With assistance from Energy Trust of Oregon, a 45-kilowatt solar array was placed on the roof of an exterior walkway along the building’s south side. The canopy not only ensures the photovoltaic panels receive sunlight, Running said, but also shades classrooms and puts less pressure on the ventilation system.

At first, even with those features, the building would have had an Energy Use Intensity (EUI) number too high to be net-zero. That number is calculated by dividing the building’s total energy consumed in one year by the total gross floor area. The new classroom building would’ve been around 20 EUI, Running said.

By the time the project team realized it wouldn’t achieve net-zero energy, it was a little late in the process; the contractor had been selected, and construction documents were completed. Now, 20 EUI would’ve been significantly lower than the state’s requirement that public buildings perform at least 20 percent better than the building code. But the team was 鈥渟o close to net zero 鈥� the cost wasn’t too much more,鈥� Running said.

Chemeketa Community College Technical Development Manager Isaac Talley then sought a grant from Portland General Electric to bridge the gap.

鈥淭here’s always the pursuit of the practical, best possible option but (a) need to balance that with what will work and the budget,鈥� Talley said.

The college also looks at what would be the 鈥渂est bang for the buck and maintaining the best functionality through the life of the building,鈥� he added.

In February, when the project was nearing substantial completion, Talley received word that the team would receive a $158,000 grant from PGE. That would put a 91-kilowatt solar array on the classroom building’s roof, and achieve net-zero energy use.

The total cost to reach that goal was around $9 million, Running and Talley estimated. That included concrete floors, insulation, window systems, an efficient mechanical system, and the original solar array.

The key to this project, Running said, was 鈥渘ot trying to do every single sustainability strategy under the sun.鈥� Instead, the team honed in on a few 鈥� one was natural ventilation inside the building, and another was solar energy production outside.

Outdoor features of the complex will include gardens and farm demonstration fields. Now the college can say it’s 鈥渉arvesting from the ground and harvesting from the sun,鈥� Running said.