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Lessons Learned from 4 Zero Energy Buildings

Sept. 22, 2017

Learn from successes and shortcomings of these net zero facilities.

BUILDING 1: Successful Retrofit: Shipwire Headquarters  
Sunnyvale, CA

As a building that started off as a nondescript, concrete building very much rooted in the aesthetics and architecture of the 1970s, 435 Indio Way wasn’t what you might expect as a candidate for net zero energy status. But with the vision of a forward-thinking developer and ownership team, this office building originally lacking any of the high-tech charms of other Silicon Valley facilities achieved zero energy after its renovation completed in 2013.

“The developer wanted to create a net zero energy building at no additional cost to what it would take to do a conventional renovation of this building,” says Steve Stenton, Director of Sustainability at RMW architecture & interiors. “The leading driver was zero energy, but equally important was creating an interior space that was comfortable and energizing by maximizing daylight, using passive mechanical airflow strategies and eliciting a connection to nature.”

Reducing Energy Use

The facility – now occupied by Shipwire, an order fulfillment software company – was certified by the New Buildings Institute and has continued to fulfill and exceed energy expectations in the years since the renovation. Reaching zero energy status occurred through a combination of using existing features of the building and introducing new technologies that are energy-efficient and promote occupant comfort.

“One important design approach was to use the existing concrete walls and floor as thermal mass to absorb interior heat during the daytime, which helps regulate the interior temperature and then gives the heat back in the evening – a process that keeps the space at a more constant temperature,” says Stenton. “Adding 5 inches of rigid insulation on the exterior of the building provided thermal separation between the exterior and concrete. The operable windows and skylights allow for both daytime airflow and nighttime flush out, which like the concrete, aids in the regulation of the indoor air temperature, minimizing the need for mechanical heating and cooling.”

To complement the stability that the concrete in the building provides, RMW also incorporated large ceiling fans that operate at a low velocity when needed, as well as desktop fans for more individualized options for occupants. “If you have slow moving air flowing across the body, it will give you the feeling of 4 to 6 degrees of temperature drop. That’s not high technology, it’s just smart design,” explains Stenton.

The facility provides more daylight with electrochromic windows that help with heat gain and glare, provide views outside and eliminate the need to put in window blinds. Additionally, light sensors were incorporated into each individual light fixture, allowing lights to act independently based on daylight conditions.

Ultimately, the changes have paid off beyond just the energy performance. While most similar conventional facilities in the area take on average 18 months to find an occupant, 435 Indio Way found one in three months. The tenants pay less in utilities as part of the green lease, and the owners have found financial benefit in higher rent and longer leases.

BUILDING 2: Improper Energy Performance Metrics: Adam Joseph Lewis Center, Oberlin College  
Oberlin, OH

If the energy numbers for high performance buildings are incorrectly calculated or misleading, certifications and claims that a building is zero energy are questionable.

The Adam Joseph Lewis Center for Environmental Studies (AJLC) at Oberlin College had been claiming zero energy performance for 11 years, and the building’s status had been highly publicized. These claims appeared on Oberlin’s website, alumni publications and news outlets including the New York Times praising its design and performance.

However, a 2012 paper written by Oberlin professor John H. Scofield refuted these claims of net zero energy, arguing that the building had been basing these claims off of misleading energy numbers – numbers that were “mathematically correct but scientifically irrelevant.”

“Sadly, the claim is not supported by the facts,” writes Scofield. “The data clearly show that, in its first 12 calendar years of existence, there is not one year in which the AJLC has produced more energy than it consumed – though it came close in 2007.”

The data the university used was flawed because it compared the average annual building energy consumption from 2002-2010 to the average annual energy production from 2007-2010. The problem with this line of comparison is that this ignores the significant rise in energy consumption that occurred from 2006-2010, thus making it appear that the building successfully achieved net zero during each of these years when it actually failed every single year.

After Oberlin hired a new building manager to solve the energy problems at the AJLC, these computational practices have been corrected, and the building is more successful in its energy goals now (2012 was the first year that the AJLC produced more energy than it consumed). Nonetheless, the AJLC serves as a cautionary tale for zero energy buildings that has cast some doubt on energy performance data.

BUILDING 3: Poor Planning of Building Materials:  Newberg Center, Portland Community College
Portland, OR

Portland Community College’s Newberg Center is a different kind of cautionary tale, as poor planning in its quest for zero energy led to major costs.

The sandwich-design roof panels used in the building failed to the extent that the college needed to replace the roof at a cost estimated at over $3 million less than four years after the building had opened for operation.

It was later revealed that officials had been notified in 2011 about the strong possibility that the roof would not last. By 2015, it had been confirmed that the roof had rotted from the very moisture issues that had plagued earlier projects.

The failure of the Newberg Center is an important reminder that while outfitting your building to become zero energy, make sure you do not get tunnel vision with building materials and systems. What might theoretically provide the best energy consumption could also be a bad choice for your building’s environment.

BUILDING 4: Effective Oversight of Energy Performance: The David and Lucile Packard Foundation Headquarters
Los Altos, CA

With conservation as one of the guiding tenets for the David and Lucile Packard Foundation since it began work in the 1960s, leaders in the organization wanted the headquarters to be an exemplar of sustainability and energy performance.

“While climate change wasn’t in the vernacular in 1964, interest in the environment surely was. When it came time to build our new headquarters, we wanted to show evidence that net zero energy buildings can work in practice,” says Craig Neyman, Vice President and CFO of the Packard Foundation.

The foundation’s headquarters, certified through the International Living Future Institute in 2013, has been in operation for five years now. In each of them, the building’s performance has yielded a surplus and exported net energy back into the grid, explains Neyman. After incorporating small upgrades largely within the first year, the building has reached a sweet spot in performance that has been maintained over time.

In addition to the energy goals for the facility, creating a comfortable and aesthetically pleasing workspace was a driving force. The building features 12 distinct architectural neighborhoods which are linked together by open spaces.

 “If you were to walk into our building not knowing it was net zero energy, I think you would say, ‘This is a rather pretty building,’” says Neyman. “It’s designed for comfort first just like any other office building, and the primary consideration after achieving that level of comfort is to do so in an energy-efficient manner.”

The facility is outfitted with 15,000 monitoring points that help make sure the building achieves net zero, and they help facilities staff quickly identify what needs attention if the building is not performing up to its standards. Moreover, the foundation is able to monitor electricity use for greater oversight of energy and plug load performance throughout the facility, explains Neyman.

For energy generation, the facility employs 915 solar panels on the roof and across the visitor parking lot that have a 300 kW capacity with the expectation of generating a minimum of 300 MWh of electricity annually.

Neyman points to three main areas where the building fulfills energy consumption requirements: plug loads, HVAC and lighting.

To reduce energy usage via plug loads, the foundation simply made use of energy-efficient appliances and equipment when possible. Occupants use laptops instead of desktop computers because they are more efficient, and there is only one printer in each neighborhood of the building. Chilled beams fulfill its HVAC needs.

The building’s narrow footprint and number of windows contribute to the amount of daylight that reaches occupants, and windows in the connector area are accompanied by small display panels that provide indications to occupants when conditions are best for them to be opened. The lights throughout have sensors that interact with the natural light, and the facility is also outfitted with occupancy sensors. 

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