The National Renewable Energy Laboratory's "net zero" building on its Golden, Colo., campus is designed and situated so as to take maximum advantage of natural lighting and shading. (Energy Department)
Two new federal office buildings are months away from becoming the first in government to operate off the commercial power grid, a landmark distinction that will set the course for all future federal construction.
The net-zero energy buildings — so named because they generate as much energy as they consume — belong to two agencies on the vanguard of scientific research and discovery: the Energy Department and NASA. Yet the new buildings rely mostly on low-tech and low-cost solutions that can be replicated across government and beyond.
"I really see this as a prototype of a 21st-century building. This is the way we're going to have to think about building in the future," said Steve Zornetzer, associate director of NASA's Ames Research Center outside San Jose, Calif.
Construction costs for the Energy building, the larger of the two, are comparable to averages for typical commercial office space. The NASA building will cost significantly more, due largely to several technological advances being tested in the building, which is dubbed the Sustainability Base.
Interest in both buildings is high. Regional officials from the General Services Administration, the federal government's landlord, have visited the Energy facility four times, said Jeffrey Baker, director of laboratory operations at Energy's Golden, Colo., field office.
"They're in awe of how we pulled this off," Baker said.
Under a 2007 federal law, all new federal buildings and those undergoing major renovations must achieve net-zero energy consumption by 2030.
Both the Energy and NASA facilities employ fairly simple solutions that will help them cut energy consumption. Windows will open and close, for example, allowing natural ventilation to largely replace artificial air. Cool air will be drawn in at night in both buildings and then distributed through a series of vents and fans the next morning.
Neither building will use conventional systems for heating and cooling. The NASA building will be heated and cooled using geothermal wells buried deep in the earth. The Energy building will be heated with air generated in the building's data center and cooled with captured air stored in an underground concrete labyrinth.
Both also will be at least partially powered by photovoltaic panels covering their roofs. NASA plans to supplement energy generated by the solar panels with a hydrogen fuel cell.
Both facilities are striving for the highest level of certification, platinum, from the U.S. Green Building Council's Leadership in Energy and Environmental Design program.
NASA's building is a 50,000-square-foot, two-story office located at Ames Research Center, near the south end of the San Francisco Bay. Construction should be completed by the end of the year. The 210 employees who will move to the new facility in the spring currently work out of two 50-year-old facilities that will be demolished.
Energy's facility, on the grounds of the National Renewable Energy Laboratory (NREL) in Golden, Colo., is much larger. In fact, it will become the largest net-zero building in the world once it opens in June, officials say.
Calculating minimal energy
Energy initially planned the new Research Support Facility as a 222,000-square-foot building, but decided to expand it to 370,000 square feet using Recovery Act funds. About 740 employees will move into the building in June; another 560 will come on board when the additional wing opens the following summer. The employees now work out of costly leased space.
Energy used a software program developed by NREL to calculate the least amount of energy it would take to operate the building. The software factored in everything that would either add to or take away from the building's energy load, including rooftop photovoltaic panels, interior lighting, computers and other electrical devices, and even how many windows should be placed on each side of the building.
"It turns out that to get very high energy efficiency very cost-effectively, it's a lot of little decisions that all have to fit together," said Ron Judkoff, principal lab program manager for building energy research at NREL.
Based on the modeling, the department set an aggressive energy goal upfront for the facility: 32,000 British thermal units (Btus) per square foot annually, including the on-site data center. That's about half the energy allowed under commercial building standards.
The maximum energy load requirement was one of the few specifications included in the department's contract proposal; contractors mostly were given free rein in proposing the building's design, size and materials to be used.
"We tapped the creativity of the private market and allowed them to come up with the best solution for us," Baker said.
The winning design resembles an H, with two 60-foot-wide wings connected by a glass-enclosed central corridor. The design and placement of the building allows the interior to be flooded with as much natural light as possible.
At NASA, natural light
Similar thought was given to designing the NASA building. The building will be only 52 feet wide, about half the width for typical office construction, and will feature floor-to-ceiling windows on both ends, allowing natural light to flood the open space. In addition, skylights will provide ample natural light for occupants on the second floor. The building should be able to operate without any overhead lights for all but about 40 days of the year, Zornetzer said.
Employees will have highly efficient LED lights at their workstations when they need to supplement the natural lighting, while the building control system will turn on the overhead fluorescent lights when needed.
"We wanted to build a building that in the long run would frankly save us money on energy costs, create a workspace that would increase productivity of our employees and just be responsible to the environment. This is one way of making a small contribution to address some of the issues we're facing as a planet," Zornetzer said.
NASA's building features a few more technical advances than the Energy facility. For example, the building will be testing out a unique water purification system that eventually will be deployed to the International Space Station. Potable water from sinks and fountains that ordinarily would go down the drain will be captured, purified and used for flushing toilets and watering lawns. NASA estimates it will use 90 percent less potable water than an equivalent building.
NASA also is developing a state-of-the-art building control system that will further improve the building's energy performance.
Being green won't break the bank
The NASA building will cost roughly $460 per square foot, compared with $250 per square foot for the larger Energy facility. Construction costs for the Energy facility are comparable to the averages for typical commercial office space.
And those figures are before factoring in projected savings in utility and maintenance costs at both buildings that ultimately will make them more cost-effective in the long run.
"I think it's a great deal for the taxpayer," Zornetzer said. "If we're successful, it's really a wonderful template for future federal facilities, not to mention the private sector."
Employees will play an important role in ensuring the buildings use the least amount of energy possible.
Last week, the 210 employees who will be moving to NASA's new building gathered for the first time to learn about the new facility and what steps will be required of them. For instance, the automated system being developed for the NASA facility will monitor how much energy employees are consuming at their work stations and relay that information to employees on their computer screens, encouraging them to unplug unneeded electronic devices to reduce consumption.
"Most of us just take it for granted — the power's there, we use it, and if we're not as aware of our own behavior and our own choices as we could be, then perhaps we'll be wasteful. So we want to try to prevent that," Zornetzer said.
Likewise, Energy is putting strict controls on what electronic devices can be brought into the building; personal coffee pots and space heaters will be banned, since they increase the energy load.
"It seems almost trivial, but the big part of the load in commercial office buildings is all the stuff that's wired in inside," Judkoff said.