Energy-Efficient Operations | An Inside Look at ASU's First Net-Zero Building

E N E R G Y- E F F I C I E N T

O P E R AT I O N S An Inside Look at ASU’s First Net-Zero Building

BY RANDY DENHAM

Strive for zero.

It’s a common mantra that usually pertains to safety, but it’s something we can now aim for when it comes to sustainability as well. With sustainability standards not only becoming increasingly stringent, but meeting or exceeding them is also the norm, design and construction teams must find innovative ways to build greener facilities that operate at peak efficiency throughout their lifetimes. This means collaborating with partners before any shovel hits the ground as well as a commitment from top to bottom during construction to ensure best practices on site, and that’s exactly what we achieved for the Student Pavilion at Arizona State University (ASU), the institution’s first net-zero building.

capable of delivering less than 65°F air on a 104°F day without any supplemental mechanical cooling, which provides very efficient conditioned ventilation to the high-occupant event spaces. The office and classroom cooling is provided by chilled beams, which efficiently utilize used/return chilled water from the campus-chilled water loop. These systems offer much more efficiency than their traditional counterparts. “The high efficiency indirect evaporative system and chilled beam system complement each other very well, allowing us to effectively condition the building with minimal chilled water from the university’s central plant” said Rob Fries, Senior ME Engineer for JE Dunn.

As an early adopter of renewable energy initiatives, ASU already has existing solar panels and power parasols to help offset the power consumption in many of their buildings. To achieve net zero, the design for the Student Pavilion went even further and incorporated solar panels on the roof to ensure power consumption was offset, as well as occupancy sensor lighting, controlled power receptacles, chilled beams, indirect evaporative cooling, and LED lighting systems.

The indirect evaporative cooling system is a large reason the facility could achieve net-zero status. The two-pass evaporative system is

In addition to the cooling system, we used occupancy sensors to not only control the lighting system, but also to manage the unnecessary plug loads at each receptacle. This came into play particularly on the second and third floors where the receptacles have one constant “on” plug and one controlled by the occupancy and/or the time of day.

“The plug load control helps reduce ‘phantom’ loads that consume power when not in use, such as computer chargers and audio/video equipment,” said Fries. “Those phantom loads are a huge energy waster in buildings of any kind.”

AS SEEN IN : SCHOOL CONSTRUCTION NEWS | JULY/AUGUST 2018 | SCHOOLCONSTRUCTIONNEWS.COM

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PHOTOGRAPHY | BILL TIMMERMAN

PHOTOGRAPHY | BILL TIMMERMAN

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AS SEEN IN : SCHOOL CONSTRUCTION NEWS | JULY/AUGUST 2018 | SCHOOLCONSTRUCTIONNEWS.COM

PHOTOGRAPHY | BILL TIMMERMAN

PHOTOGRAPHY | BILL TIMMERMAN

While the goal of a net-zero building is to use the same amount “We didn’t want to put anything in the landfill if we didn’t need to, of energy as it creates through renewable components annually, so we sorted—and resorted, if necessary—all recyclable materials to other strategies, including the envelope itself, played a huge role in ensure it was done correctly. This was more challenging as we moved achieving the desired sustainability. Architect Phil Weddle and his upward and the building was enclosed, but with a dedicated team team first took a comprehensive look at the design to see where they and buy-in from all trade partners, it made a huge impact on the could reduce energy levels for the LEED-platinum building from the overall project,” said Senior Manager Clay Creaser. start. “Before we started designing, we evaluated ways to maximize The effort did not stop with the laser focus on traditional recycling passive strategies. This included daylighting, building orientation, methods, however. While waiting for rooftop drain lines to be and the envelope. Using orientation combined constructed for landscape irrigation, the with 100 percent LED lighting allows the team skipped the installation of separate and daylight work naturally, helping reduce energy temporary water lines in favor of a more demand. We also took advantage of insulation eco-friendly option. Instead, they built lines “ We didn’t want techniques in the envelope to increase to buckets and used condesate to water palm to put anything in sustainability. By ventilating the façade with trees until the actual lines were in place. That copper on the upper skin, hot air that rises up the landfill if we zero-waste mindset also sparked an idea from now vents out the top of the building, which didn’t need to, foremen and laborers: recycle the shavings, minimizes heat infiltration,” he said. “We so we sorted— dust, and residue from ground concrete. The looked at all of these factors, even selecting team used the concrete dust created from floor and resorted, if materials based on their embodied carbon polishing activities and mixed it with water, necessar y—all and using resources closer to the job site, creating solid chips they could then recycle and before determining any of the building systems. recyclable materials saving even more waste from the landfill.

This enabled us to enhance the sustainability to ensure it was features inside the building once we Conserving waste literally from top to bottom— done correctly ” determined a solid energy-saving foundation from the redirected condesate water on the roof outside.” to concrete dust on the floors—was a complete

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It’s easy to quantify efficiencies in the design, but another aspect of the team’s commitment to achieving the goal of zero was the total buy-in to waste diversion in every facet of construction on site. Merging innovative ideas with traditional recycling and paperless practices resulted in not only a green site, but also left a smaller footprint once construction was complete.

team effort, and the result was a facility that is both stunning and sustainable. “Even with a culture of Strive for Zero, it was an extra effort for our people,” said Creaser. “We put such a focus on it, from the design of the building itself to construction, that it was part of everyday operations. When you set the same expectations regardless of sustainability goals, it makes a big difference.”

AS SEEN IN : SCHOOL CONSTRUCTION NEWS | JULY/AUGUST 2018 | SCHOOLCONSTRUCTIONNEWS.COM

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AS SEEN IN : SCHOOL CONSTRUCTION NEWS | JULY/AUGUST 2018 SCHOOLCONSTRUCTIONNEWS.COM