I'm working on a story for AIArchitect this week that focuses mainly on the economics of building a solar-powered house for the Department of Energy’s Solar Decathlon, but I don’t want all this talk of owner ROI and scales of prefab production to get in the way of a good design conversation.
So: This year, more so than the last competition in 2007, marks an important signpost on the road to net-zero energy homes required for such buildings to ever be mass produced and palatable to a wide range of consumers.
Basically, I noticed that the houses all looked quite a bit different from each other.
All these different materials and spatial organizations are making it clear that solar-powered residential design is germinating and evolving in different directions. Instead of the gabled-by-default rectangle lined with PV panels on sloping roof planes that will probably be considered the Model-T of the sustainable building world, student teams this year have moved further and further into rigorously planned and rich expressions of sustainability. There’s the cool stone materiality of the Team Alberta group, and the gritty, steel-ribbed brawn of the University of Arizona house. Wood is still a popular material to build with, but more and more teams are using high-tech plastic composites and lining walls with PV panels (like Team Spain and Team Germany). Vernacular architecture references are getting more subtle and understated, and in some ways more ambitious. Cornell University’s house is organized around three cylindrical volumes the explicitly resemble the rural silos of upstate New York. The houses don’t look uniformly “green,” and that’s a good thing.
The decathlon teams are getting more and more comfortable with simply integrating photovoltaic panels into their designs as well. In past years, some teams built houses that required over-large metallic armatures to support excessive PV panels that unbalanced their designs, but were required to power the house. This year, more teams are making sure they’ve dealt with passive sustainability features (solar shading, air circulation corridors, solar orientation, etc.) as rigorously as possible, keeping total energy needs to an absolute minimum. The results are houses that don’t scream “SOLAR POWER!” with a caffeinated earnestness. And they’re more pleasing aesthetic objects, too.
Now, back to the serious economics stuff. It’s a not a great analogy because cars are far from ideal in terms of sustainability and energy consumption, but it looks like the 2009 Solar Decathlon represents some of the first few assured steps away from the “You can have any color as long as it’s black” Model-T and toward the innumerable bells, whistles, shapes, forms, and brands of the modern automobile industry. (Which, incidentally, is also trying to redefine itself in an age where carbon emissions come with a cost. Maybe the two industries can learn from each other.) But it’s this product variety and versatility that consumers demand, and it’s what will win them over. With a broad consumer base established, solar houses will become more and more affordable. The best solar-powered houses are upfront about what kinds of things people have to give up to preserve human’s balance with nature. Good design isn’t one of them.
(Above: Cornell University and Team Germany's soalr houses. Photo Credit: Stefano Paltera/U.S. Department of Energy Solar Decathlon.)