WUSTL wins award for case study of Living Learning Center

Award recognizes honest disclosure of lessons learned in constructing a building that required zero net-energy input

The Living Learning Center at WUSTL’s Tyson Research Center has been certified as a “living building,” one that requires no more energy than it produces, requires no more water than it captures, and produces no waste, but it needed a bit of coaxing to get there.

The Association for the Advancement of Sustainability in Higher Education (AASHE) named Washington University in St. Louis as the winner of its “Best Lessons Learned Case Study Award” Oct. 11 during the AASHE 2011 Conference in Pittsburgh.

The award was for the case study, “Getting to Net-Zero: Lessons Learned from a Living Building Challenge,” which outlined “the mistakes, corrections, and lessons learned that ultimately led to successful certification” of WUSTL’s Living Learning Center at Tyson Research Center as one of the first net zero energy “living buildings.”

Kevin G. Smith, associate director of the Tyson Research Center a 2,000-acre environmental research station located 20 miles west of the university’s Danforth campus, and adjunct professor of biology in Arts & Sciences, accepted the award durring AASHE’s Sustainability Awards reception.

“AASHE is proud to honor Washington University with this award, affectionately referred to as the ‘oops award,’” says Paul Rowland, executive director of AASHE. “The award recognizes the best case study of a project that didn’t go as planned and that offers important lessons for others.”

“Oftentimes, stories of projects that don’t go as planned can be really helpful, but campuses can be hesitant to tell such stories,” Rowland says. “Campuses willing to go out on a limb to try something new deserve credit for trying and are doing the rest of the field a favor.”

AASHE is an association of colleges and universities in the U.S. and Canada that are working to create a sustainable future. Its mission is to empower higher education to lead the sustainability transformation by providing resources, professional development and a network of professional support.

The winners of AASHE’s 2011 Sustainability Awards will be featured in the December issue of Sustainability: The Journal of Record.

Flaws and fixes

In 2008, Washington University committed to the construction of a new building at the Tyson Research Center that would attempt to meet the rigorous Living Building Challenge. Introduced by the Cascadia Region Green Building Council and now administered by International Living Building Institute, the Living Building Challenge strives to achieve performance levels beyond those prescribed by LEED and other green building rating systems.

In particular living buildings must achieve zero net energy, zero net waste and zero net water usage. Of these challenges, the most difficult proved to be that the building expend no more energy than its generated (with solar panels) over the course of a year.

Adding to the challenge, the building had to be designed and built in only nine months, and at a time when the U.S. economy had just entered a recession. Some of the problems that later arose could be traced to efforts to cut all unnecessary costs in a “value engineering” overhaul of the original design triggered by the economy.

Performance monitoring after the building was completed showed that it consumed more electricity than the photovoltaic panels produced, especially during the cold winter months, and the construction team reassembled to discover and address the reasons for the shortfall.

Where was the energy escaping? The original design had called for SIP panels, exterior walls constructed offsite as one solid piece. SIP panels have “incredible insulation value” Smith says “because there are no gaps through which air can penetrate the building. But they are also very expensive and to hold down costs, we switched to wood frame and batt insulation construction.

One of the remedial steps the team took, therefore, was the mundane one familiar to every homeowner of making the building tighter by sealing, insulating and installing storm panels.

What else was wrong? To keep the air from becoming stuffy when the building was occupied, the heating, ventilating and air conditioning system sometimes had to bring in fresh air. To minimize energy loss, carbon dioxide sensors in the classroom triggered the operation of a heat pump and heat exchanger. The heat pump had a variable refrigerant volume, so no energy was wasted expanding and condensing refrigerant not needed by the heating or cooling load, and the heat exchanger captured some of the heat from the exhausted air and transferred it to the fresh air.

But the heat pump system did not perform as specified, which “comes with the territory when you install new technology that wasn’t tested under the conditions identical to those of your installation,” Smith says.

To reach zero net energy, the team had to add sun-tracking photovoltaic arrays to supplement the generation capacity of arrays installed on the building’s roof.

Once the team had tweaked the heat pump’s performance, they monitored the building’s energy performance and then added just enough photovoltaic generating power to make up the difference.

“We had cut too much in the initial cost review,” Smith says, “because we were too optimistic about the building’s efficiency.”

Once the fixes had been made, the building began to operate at net-zero, generating as much energy as it consumed, and in 2010 it was certified by the International Living Building Institute as one of the first Living Buildings.

Lessons learned

The key point, Smith says, is that it wasn’t technical expertise that made the difference. “What made us successful was the dedication and commitment of everyone working on the project,” he says.

“As you can imagine, when you’re finished with a construction project, you don’t want to go back and do more work on it. And what was amazing to me is that everyone — the architect Daniel Hellmuth, the project manager Neal Schaeffer, the engineers led by Matt Ford, the contractor, Justin Bingman and Tyson’s maintenance manager, Peter Jamerson — was willing to come back and work through these issues with us. They understood this wasn’t just any old project; they knew they had signed up for something big, and that it would be challenging, and they were willing to hold themselves accountable.”

“The real reason we achieved net-zero was that the whole team remained committed,” he says.

One of the requirements of the Living Building Challenge was that the building include design features intended solely for human delight, such as this rain flower designed by artist Hap Phillips for the rain chain that guides water from the roof to a rain barrel.

Another lesson Smith draws is that energy conservation is more cost-effective than renewable energy production. “We’re tempted to think of renewable energy as a panacea,” he says. “But when you get right down to it renewable energy is still energy, it’s still expensive, it’s not something you should waste. So the right approach is to build the most efficient building you can and then provide it with the least amount of energy generation you can get away with.”

And as the old carpenter’s adage has it, “measure twice and cut once.” Had they had more time, the team might have avoided some problems by modeling the building’s energy needs before construction, and commissioning the building at occupancy (checking to make sure all the systems are working as they’re designed to work).

The building challenge did not require these steps, Smith says, but they turned out to be necessary to meet the challenge.

And finally, Smith says, construction happens once but energy use is forever. Given the experience with the Living Learning Center, value engineering reviews now take account not just of the immediate costs but also of the long-term impact of cost cutting on performance and energy efficiency.

“I think it says a lot about everyone involved that we’re willing to own up to these mistakes — not only to fix them but also to share them with other people in order to help everyone who is trying to build a building like this. I think that this is a big part of what being a university is about,” says Schaeffer. project manager in Facilities Planning and Management and a co-recipient of the award.

The rolling wooded hills of the Tyson Research Center near Eureka, Mo.