Where are They Now?
Appears in the Summer 2018 issue.
Revisiting Previously Featured Buildings
Designing a building is a tough business. Months or years can be spent on one project, and then it is on to the next one. Often, designers know how the building performed during the first year of occupancy. But how do designers capture the lessons learned over time?
High Performing Buildings magazine checked in with three of its featured buildings to see how they have been performing and to find out what the engineers wished they had done differently or had known during the project.
Two buildings, the Federal Center South Building 1202 in Seattle and Oakland University’s Human Health Building in Rochester, Mich., have been in operation since 2012. After more than five years in operation, energy savings and system performances in each building have been tracked, analyzed and adjusted.
The other featured building, the Rocky Mountain Institute Innovation Center in Basalt, Colo., has been occupied since 2016 and has become an industry example of how to achieve net zero energy in a cold climate.
From building operations to occupant feedback, engineers discuss what has changed since the buildings opened and lessons they learned from the building.
Federal Center South Building 1202, Seattle
Behind the sleek, stainless steel exterior of the Federal Center South Building 1202 is a rough-hewn timber interior environment. Originally featured in the Fall 2014 issue of HPB, the building is the result of a design competition and innovative systems.
The Federal Center South Building 1202 in Seattle is the result of a 2009 design competition, and about 10 years later, the building’s innovative systems have produced satisfied occupant feedback.
Functioning as the Seattle district headquarters of the U.S. Army Corps of Engineers, the building was the result of a guaranteed performance-oriented contract—a first for the U.S. General Services Administration.
It has been just under six years since the Federal Center South Building 1202 reached substantial completion and occupancy, and almost four years since a feature on the building ran in the Fall 2014 issue of HPB.
According to the original HPB feature, “the guaranteed energy performance target required the building team to meet an energy goal 30% better than the ASHRAE/IESNA Standard 90.1-2007 baseline model, or an effective EUI of 27 kBtu//ft2.yr, with 0.5% of the overall contract award retained until the first year of performance was verified through a measurement and verification (M&V) process.”
The M&V process spanned one year after the building was in operation, and during that period, the engineering team remained involved in making sure the building was performing as designed and as modeled, said Charles Chaloeicheep, P.E., Member ASHRAE, who served as the project’s design energy modeler.
After that first year, they stopped monitoring the building’s processes, but even with a lack of performance data, Chaloeicheep recalls comments from the building’s occupants and lessons learned from the technologies used and the project experience.
Chaloeicheep said sometimes M&V consultants have access to building data after the process is over, but sometimes owners lock down the building’s data and no longer share it with an outside agency. He said he recommends people continue to share the building information in case someone wants to perform a M&V exercise about five years after building operation.
The skylit central atrium forms the social heart of the building. The building’s bones use systems like boilers and chillers that were adjusted to increase energy efficiency.
When the building opened, some systems had to be adjusted to perform properly, he said.
“When we first opened up, they were using the boiler a lot more than we were anticipating,” he said.
The building has a backup boiler system and heat recovery chillers that recover heat from the group loop system integrated into the structural pile as well as from thermal store, he said. Chaloeicheep said it seemed as if the sequence had been set up to use boilers for heating and chillers for cooling, so the team made adjustments to the setpoints for modes of operation, making it more energy efficient.
The occupants are not using the building’s boilers as much and are relying on heat recovery chillers and the ground loop, which Chaloeicheep said is a good indication the building’s systems are still performing well and are on the “tuned path.”
New vs. Proven
The design team for Federal Center South Building 1202 used innovative strategies such as modeling tools during the design process to consider and test different ideas to hit the energy target, said Chaloeicheep.
For example, the building’s passive chilled beams are unique to Seattle and the Pacific Northwest, and the building’s thermal storage with base change material is also different in the region, Chaloeicheep said.
While Federal Center South employs innovative technology, Chaloeicheep said he has learned throughout his career to stay open-minded when considering implementing new technology and proven technology. He said buildings that use proven technology as opposed to the most innovative systems at the time can achieve similar performances to Federal Center South.
“Sometimes people want to do very innovative systems or very innovative solutions. I’m all for that, but I also feel like sometimes people can be too hung up on that and try to push too hard to try something new when there’s a lot of great, proven technology out there,” he said. “It’s good to recognize that there are different ways to get to your target. One isn’t necessarily better than the other.”
Expanding the M&V Process
The Federal Center South Building 1202 required a one-year M&V process that mainly focused on energy, Chaloeicheep said. If he could change something about the project, he said he would integrate thermal comfort, water, air quality, lighting and visual comfort into the M&V process, making it more robust.
“There was a good thermal comfort dynamic that we also looked at, but it wasn’t part of any contractual requirement,” he said. “It would have been great to look at the comfort in the space.”
Federal Center South Building 1202’s M&V process during the first year focused mainly on energy, but the project’s design energy modeler said he wishes thermal comfort and other considerations could have been integrated more into that process.
© Benjamin Benschneider
Luckily for Chaloeicheep and other key players such as the architectural firm and builder, the team worked together on another project in Washington. They were able to apply the lessons they learned from Federal Center South to the second project, a new Washington State patrol office building in Olympia, Wash.
“Now over there (in Olympia), we’re looking at water more closely, and we had a little bit different system because of the size of the building. We wanted to look at thermal comfort and giving people a little bit more control over their environment,” he said. “We learned lessons, and we were able to apply them within a few years.”
Rocky Mountain Institute Innovation Center, Basalt, Colo.
The Rocky Mountain Institute Innovation Center meets more than 100% of its energy needs with on-site photovoltaics and other systems. Featured in the Spring 2017 issue of HPB, RMI eliminated central cooling and reduced heating to a small distributed system.
© Tim Griffith
The Rocky Mountain Institute Innovation Center in Basalt, Colo., not only proves net zero energy can be achieved passively in cold climates, but was designed to be replicable, said Cara Carmichael, manager of Rocky Mountain Institute’s Buildings division.
The Innovation Center, located about 19 miles northwest of Aspen, Colo., reached substantial completion and occupancy in 2016 and was featured in the Spring 2017 issue of HPB.
At the Innovation Center, RMI was able to eliminate central cooling and reduce heating to a small distributed system while meeting more than 100% of the building’s energy needs with on-site photovoltaics after investing in an airtight envelope, three times the code-required levels of insulation and an active strategy to manage solar gain, according to the original article.
The Innovation Center was designed to have a four-year payback, and is well on its way to meeting that goal, according to RMI.
“The results for the past year are even better than I anticipated,” said Carmichael.
The building was modeled for a 17.2 kBtu/ft2·yr EUI, but the total EUI was 12.5 kBtu/ft2·yr in 2017. Video conference equipment is the biggest end user of electricity. The center’s solar PV is performing three times better than modeled. The center has also earned the Living Future Institute Petal Certification.
When the building was first occupied, the staff had to make a few adjustments with the open-office environment, Carmichael said.
One, the center’s acoustics were different from what the staff was used to, she said. Conference rooms and phone booth areas for people to make private calls were designed to help manage the acoustics, according to Carmichael.
RMI’s staff had to adjust to the new open office environment and its acoustics. The building’s materials were carefully selected to ensure a sustainable and durable state-of-the-art office.
There have also been adjustments made to the physical building since it opened. Several windows, all under warranty, were replaced on the side of the building due to some buckling of the heat film on the interior of the window assemblies. This did not have an observable effect on the performance of the building, according to RMI.
Carmichael said the metering and controls were the “biggest miss” in the building.
The submeters and controls were initially designed to talk to each other and gather information in the same location, but that was a challenge, she said. RMI tried to use BACnet-compatible controls, but some of the systems, like sunshades and the battery storage, were so specialized that they did not connect yet but use a separate controls system.
“The meters seemingly frequently go down, and we have had to keep an electrician on contract to help correct those issues,” Carmichael said.
Carmichael said if she could change something, she would have pushed harder to simplify the meter and monitoring system further.
“It was a goal in the beginning, and we knew we wanted as simple of an interface as possible. It just wasn’t possible in the industry,” she said.
RMI had five key lessons learned from the Innovation Center that the organization has used to inform other projects:
- A whole systems approach makes achieving net zero energy cost-effective. Three factors provided operational cost savings for the center’s four-year payback on net zero energy: reduced energy costs, reduced maintenance costs and increased productivity and satisfaction.
- Commissioning and monitoring are critical in meeting net zero energy goals.
- “RMI’s one-year commissioning process revealed improvements that were essential in ensuring building systems and technologies were operating as designed. Dedicating the time and cost for a commissioning agent was a worthwhile investment that the team would advise for any future project,” according to RMI.
- Occupant engagement and education are required. Six of the building’s 16 energy loads are entirely within an occupant’s control, and occupant engagement has been critical in maintaining performance levels over time.
In the center’s thermal comfort strategy, occupants have greater control over maintaining personal comfort with low energy using distributed technologies. RMI learned early that the lower setpoint of 64°F (17.8°C) was too cold for staff, and raised this to 67°F (19.4°C).
Given the building’s insulation and thermal mass, RMI had enough of a safety net in the passive design to make this adjustment without sacrificing building performance. In staff surveys, 74% feel that the building increases productivity, and 88% of staff feel satisfied with the levels of comfort in the building. With the building in use, RMI said its assumption that productivity would increase by 3% is likely conservative.
Integrative project delivery (IPD) is a useful process to manage cost, contracts and risk, and effectively aligns with incentives and decisions.
The Innovation Center’s solar photovoltaic system is performing better than expected and is generating three times the center’s annual energy use.
© Tim Griffith
“IPD ultimately benefited RMI’s bottom line, and all team members participated in the risk/reward pool. Keys to success for this process included a project team training to set the ground rules for the working relationship, and focused onboarding of new team members to ensure the project goals were clear to everyone,” according to RMI.
There remain major market gaps in metering and controls to successfully operate an integrated, net zero energy building.
“As you increase the number of simple, targeted systems controlling comfort, you exponentially increase the complexity of controls integration and operation. There is a big opportunity for controls to use artificial intelligence for predictive control. Instead of setting rigid, preprogrammed control sequences, technology is emerging allowing the system to learn from past performance and tune the future approach,” according to RMI.
RMI prioritized resilience features to protect the building against threats. The Innovation Center is designed to be a 100-year building and “future-proof.”
The building’s high quality materials and attention to detail in sealing the building envelope makes it durable. It can maintain a stable temperature of about 74°F (23.3°C) in different seasons and weather conditions.
RMI’s goal to make it “‘future proof” means attention to design details that could allow RMI to replace certain technologies over time to stay on the cutting edge without having to make major renovations to the building.
RMI estimated more erratic weather patterns and potential flooding, according to the results of a climate change study.
Summers and swing seasons could be warmer, so RMI employed the exterior sun shade system and natural ventilation strategies. There is also space in the mechanical rooms for active air conditioning to be added later if needed, according to RMI.
Although the center is located outside of the adjacent Roaring Fork River’s 500-year floodplain, the building site was raised five more feet for increased protection.
The roof’s butterfly design allows the building to filter rainwater and snowmelt off the roof and into a water feature that channels the water away from the building into a bioswale. The water management features on site have performed well with heavy rains.
The Innovation Center is resilient to grid failure through its ability to produce and store renewable energy on site. The building’s 83 kW solar PV system is performing better than expected and is generating about three times the center’s annual energy use. “We are running at a net positive—the building produces 146% more energy than it uses annually,” according to RMI.
The center’s 43 kWh battery storage system is programmed to hold energy demand below 50 kW. The center’s energy demands typically are below 10 kW, so RMI has yet to use the battery for demand charge management.
“The battery therefore provides a buffer for future increases in loads,” according to RMI.
Oakland University Human Health Building, Rochester, Mich.
Oakland University’s Human Health Building was desgined with “quality of life” in mind. Originally featured in the Winter 2015 issue of HPB, the building’s occupants seem pleased with the building’s comfort and environment more than five years after the building opened.
© Prakash Patel
Oakland University’s Human Health Building houses the university’s nursing and health sciences schools, so the designers focused on energy efficiency and “quality of life.”
The design includes an integrated site, building massing and orientation, solar shading and daylighting strategies, according to the original article featured in the Winter 2015 issue of HPB.
Located in Rochester, Mich., about 30 miles northwest of Detroit, the building is one of the university’s lowest annual energy user per square foot.
The building was substantially completed and occupied in August 2012.
George Karidis, P.E., Member ASHRAE, said occupant complaints about space comfort, quality of air and the building’s environment are almost “nil.”
In January 2013, the building’s total electric consumption was 298,202 kWh. Five years later in January 2018, the total electric consumption was 216,334 kWh.
Informal collaborative spaces for students and faculty are desired to supplement this mostly commuter campus. The building also houses simulation labs to simulate advanced nursing care.
© Jason Robinson
Regarding domestic water consumption, the building used 38,000 gallons in January 2013, and only 17,000 gallons in January 2018.
According to the original article, the building’s energy systems contribute to a net EUI of 56.9 kBtu/ft2 per year, which includes 8.3 kBtu/ft2 for natural gas and 48.6 kBtu/ft2 for electricity. The building uses an additional 3.1 kBtu/ft2 from the on-site solar thermal and PV panels, resulting in a gross EUI of 60 kBtu/ft2. The net EUI represents 45% less energy use than the average commercial building in this climate zone, and 50% less than one of similar size, according to the original article. The geothermal heat pump system with variable refrigerant flow, solar thermal heating panels and high efficiency fan coil units were some of the original biggest contributors to energy savings.
One of the lessons learned in the original HPB article focused on the building’s variable refrigerant flow (VRF) controls.
VRF manufacturers were improving customization abilities when the building was being designed, so control capabilities and flexibility were limited and varied based on manufacturers. The article said the VRF system could not communicate directly with associated variable air volume (VAV) boxes providing ventilation air to each space as originally planned, and adding a second parallel building automation system network throughout the building was not in the budget.
“As a result, the VAV boxes were installed with ‘stand-alone’ controls, and no ability exists for the BAS to remotely monitor the ventilation VAV box operation,” according to the article.
Since the building opened, the latest generation VRF controllers were installed to narrow room temperature swings from 4.3°F to 2°F (2.4°C to 1.1°C), according to feedback from Oakland University.
Karidis also said early failures in the chiller-heater compressors were solved by time-in/time-out settings and relying more on a small, high-performance condensing boiler.
Solar, Water Lessons and Progress
The university invested in a solar thermal system, and the team wanted to maximize summer heating capabilities. They decided on using desiccant dehumidification during warm and humid weather, according to the original article.
The building’s solar thermal system includes insulated underground storage tanks that act as a high-grade thermal flywheel, allowing for surplus heat gathered by the solar thermal system on sunny/dry days to be used on cloudy/humid days.
Karidis said the thermal storage tank has been engaged for peak storage but not yet for its intended dehumidification regeneration.
No matter how long a building project takes or how long it has been since the project ended, lessons learned never leave and can be applied to subsequent buildings. Revisiting old projects to see how they have performed over time is a rich source of new lessons learned, and looking back helps improve the performance of the built environment of the future. •