The US Department of Energy High-Performance Buildings Database is an intriguing source of information for green design. On the positive side, it presents design intents (including architectural vision) and performance strategies for 125 progressive buildings, as well as links to sources and contacts. On the other hand, many entries dwell on the acquisition of LEED points, present only modeled performance “data”, gloss over any interesting problems that may have arisen, and show no evidence of post-occupancy investigation.
At least two of the buildings in the list, however, present honest, detailed, useful accounts of their experiences: the Adam Joseph Lewis Center for Environmental Studies at Oberlin College and the Environmental Technology Center at Sonoma State University. Interestingly, these are both university buildings dedicated to environmental studies; with luck, more submissions will follow their examples! Here is a bit about the first one.
Adam Joseph Lewis Center for Environmental Studies at Oberlin College. With a design team led by passionately idealistic professor, David Orr, equally visionary architects at McDonough + Partners, and outstandingly generous donors in the Lewis family, this building was privileged from the beginning. Few of its contemporaries would be able to support a living machine, for example! But many of its features are widely relevant:
- elongated form to maximize permeability to light and air
- east-west orientation to simplify shading
- passive solar heating design incorporating thermal mass (not a simple choice in a cold winter climate)
- radiant heating in large open areas, such as the atrium, that have high infiltration
- a geothermal heat pump
- daylighting with photosensors to dim electric lights
- an outstanding low lighting power density of 0.9 W/sf
- automated operable windows for passive ventilation and cooling
- demand (CO2)-controlled ventilation to save fan energy
- very expensive highly-insulating glass
- a stunningly large 4,000sf photovoltaic array (an imperfect answer to the ideal of “sustainability”)
All of these features have been debated in projects I’ve worked on in the last year: they are gradually entering the mainstream, and owners and architects are in need of solid precedent studies.
The exceptional part of the Lewis Center effort is the commitment by both Oberlin staff and students and NREL scientists to evaluate the performance of systems in their contexts, to make both big changes (e.g. replacement of the original electric boiler with a ground-source heat pump) and small ones (controls adjustments) and to track the effects of changes. An excellent real-time display is provided on the Oberlin website, and field work results by Paul Torcellini and colleagues at NREL are also now a public document.
So: how well does this building perform? The answer is: quite well! It has an EUI of about 32 kBtu/sf-yr, met entirely (on an annual basis) by the PV array. This is about 1/3 of the EUI of other Oberlin buildings. Is it “really” net-zero? Some purists argue persuasively that the point of a net-zero building is not to offset energy use with enormous arrays of silicon wafers, glass, and metal. We’re working on a net-zero K-12 school now that’s seeking the same vast-PV solution, understandably – getting heating loads down, after a point, is just really, really hard. In any case, Oberlin has taken a fantastic step forward for all of us – not only by creating this progressive building, but by sharing their experiences, good and otherwise, with all of us.