LISI, by Team Austria, was the winning entry in the 2013 U.S. Department of Energy Solar Decathlon.

LISI, by Team Austria, was the winning entry in the 2013 U.S. Department of Energy Solar Decathlon.

Credit: Courtesy Deane Madsen


Our once-structured pace of study has fallen off significantly as we’ve each been called to take a break from studying and, ahem, get back to work. Though I brought my study materials with me on a recent visit to the 2013 U.S. Department of Energy Solar Decathlon in Irvine, Calif., I’ll admit that I used the red-eye flight home to sleep, instead of catching up on reading. Luckily, the Solar Decathlon winners employ design strategies that relate to concepts covered in LEED, so this week’s blog post will investigate how principles that the winning teams used might apply to people studying for the LEED Green Associate exam.

Europe is ahead of the game

It was difficult to escape the reality that the U.S. Solar Decathlon was dominated by the Europeans. With teams from Austria and the Czech Republic finishing first and third, respectively, it’s perhaps worth asking, how did this happen?

In beginning to answer this question of how Europe got so far ahead of the U.S. in implementing green strategies, it seemed prudent to investigate historical references to green building in both regions. And, with the LEED Green Associate Exam on my mind, it also seemed appropriate to consult the resources in front of me in hopes of finding such information.

The second edition of the LEED Core Concepts guide addresses the history behind green building in ways the first edition did not. Both editions devote a few pages to the missions of the USGBC, the GBCI, and LEED, which contribute, as Hallie noted early on, to LEED’s ecosystem being “designed to self-sustain.” For that ecosystem to support itself, it would perhaps be unwise for the USGBC to point out the benefits of other like-minded organizations—such as Singapore’s Green Mark, which Hallie discussed in her Week 3 post—even if such knowledge might empower LEED acolytes with additional tools to support the USGBC’s mission, reprinted below from the USGBC website:

“To transform the way buildings and communities are designed, built and operated, enabling an environmentally and socially responsible, healthy, and prosperous environment that improves the quality of life.”

Certifying a project through LEED certainly isn’t the only means of achieving a healthy environment—as our European counterparts can attest—nor is it the only way to transform the process of designing buildings and communities. But studying LEED is the only way to pass the LEED Green Associate Exam.

Fortunately, the second edition of the study guide contains a few more pages on the rise of the global green building industry, acknowledging in an introductory paragraph that certain green building techniques related to passive design have been in use for centuries. Unfortunately, the focus of the USGBC’s history lesson begins with its founding in 1992, although most sources I’ve consulted—including the USGBC’s online resources—point to the early 1970s as being the starting point of the modern-day green movement.

In brief, with the advent of cities’ glass-and-steel skyscrapers came the need for giant HVAC systems dependent on fossil fuels for heating and cooling the expansive enclosed spaces, but according to a white paper on sustainability produced by Building Design & Construction magazine, “it was not until the OPEC oil embargo of 1973 that the nascent ‘environmental movement’ captured the attention of the public at large.” Following the embargo, and perhaps in response to the 1972 U.N. Conference on the Human Environment, the U.S. Department of Energy was founded to address energy and environmental challenges on a national scale; and the AIA formed a Committee on Energy in 1973, which morphed into the current Committee on the Environment (COTE) in 1989.

Herein lies the apparent divergence between the green building philosophies of Europe and of the U.S.. Although the OPEC embargo did temporarily awaken the U.S. from its dream of multicar households and unending freeways—not to mention consistently comfortable 72 F interiors across the country—an abundance of land and resources propelled the U.S. back into its reverie. With average single-family homes growing ever larger over time into the 10,000-square-foot McMansions that celebrities endorse and laypeople either envy or despise, Americans have grown accustomed to living their dreams in constant, air-conditioned bliss as sprawl allows unfettered growth into a seemingly endless supply of land. Europeans, meanwhile, have had density thrust upon them beneath the pressures of population growth restrained by tight land masses, meaning that they have had to do more with less. A quick look at average home sizes in 2011, compiled by the BBC, tells the story graphically:

House sizes in square meters.

House sizes in square meters.

Credit: Courtesy BBC


Doing more with less in Europe extends beyond floor areas to include resources as well. Germany has developed a Passivhaus strategy that minimizes homes’ impact on fossil fuels by encouraging airtight enclosures and providing guidelines for caps on energy consumption: Under the system, “the use of specific primary energy for all domestic applications (heating, hot water, and domestic electricity” must not exceed 120 kWh per square meter in total.”

Elsewhere, the U.K. started the Building Research Establishment Environmental Assessment Method (BREEAM) for buildings in 1988—a program that has since expanded to be worldwide in scope. The European GreenBuilding Programme had more than 738 registered GreenBuildings as of 2012. Looking at countries beyond the U.K. and Germany, there’s no shortage of certification entities in Europe to encourage, quantify, and celebrate energy-efficient buildings.

Back at the Decathlon in Irvine, both Team Austria and Team Czech Republic embraced strategies that have been deployed in Europe for the last few decades to create comfortable environments with plenty of natural ventilation. The thick walls of each structure followed principles set forth in Passivehaus guidelines, providing thermal mass to insulate the homes against heat gain. External shading devices detached from the main dwelling spaces gave additional protection from passive solar gain, while oversized operable windows and doors allowed cross-breezes to flow through the main living areas. While, in my opinion, U.S. teams typically concentrated their efforts on using as many solar panels as possible to offset the energy loads of the most efficient HVAC systems they could find, the European teams chose not to turn theirs on, instead relying on natural ventilation. Perhaps that’s the biggest lesson from the Solar Decathlon: that having a comfortable space is as easy as opening a window.

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Please continue to send comments, criticisms, and notes on topics you’d like addressed to hbusta@hanleywood.com, @HallieBusta, or @Deane_Madsen.