The National Mall was transformed into a futuristic commune
for the past two weeks as 20 teams from four countries
erected solar-powered homes.
The bright future of green living has been on display for the
past two weeks at the National Mall in Washington, D.C.,
during the Department of Energy's 2009 Solar Decathlon. The
biennial contest, which wraps up this weekend, brings
hundreds of university students from around the world to
a temporary solar village for two weeks, where spectators can
walk through student-designed houses and marvel at the latest
green tech.
These solar homes have it all, including things that aren't
commercially available yet -- like self-activating
curled-metal shades; walls made of plants, both living and
recycled; and roofs that tilt at the sun, making them
efficient sun-catchers from Phoenix to Fargo. Worried about
efficiency while you're away? How about an iPhone app that
controls your entire house?
Teams include engineering, architecture, graphic arts and
marketing students, who typically wouldn't work together
until they reach the workforce.
Team Germany's "surprising" design took first place overall,
partly because their house performed so well in the net
metering contest, which measured how much net energy the
house produced and consumed throughout the competition. The
house had solar panels on the walls as well as the roof,
which improved its performance even with cloudy conditions.
Team Germany scored 150 of 150 points in net metering,
catapulting them over the University of Illinois at
Urbana-Champaign to win the title.
Aside from being an unrivaled educational opportunity, the
decathlon is a proving ground for a new generation of
energy-efficient products and designs. Some, like floor
heating tubes warmed by the sun, seem so obvious it's
a wonder every house doesn't already have them; others are
most certainly modern.
A few stand-outs:
* Team Arizona's hinged roof, which moves to match the
angle of the sun's rays
* Team Missouri's eco-roof and wall materials, harvested
from crops grown in the state, including sorghum and oak
* Team California's instantly-hot showers, which work by
circulating water through a heat pump activated by a bathroom
motion detector
* Team Boston's micro-inverters, which power a few solar
panels each and cost a fraction of the price of a regular
photovoltaic electricity converter
* Team California's and Virginia Tech's use of iPhone
apps to control the homes' solar-electric, entertainment,
heating and lighting systems
* Team Boston's windows, developed with Hunter-Douglas,
which combine gas, gel and air layers to form
a heat-absorbing wall when the sun hangs low in the winter;
heat radiates throughout the house when the sun sets.
"You learn skills like communicating, team-building,
executing, all these things -- we call it Startup 101,"
said Preet Anand, a senior at Santa Clara University in
Santa Clara, Calif., who is the lead water engineer on Team
California's Refract House. "What we have learned ... you
can't compare that to any other college experience."
Part of the decathlon's mission is to speed up delivery of
emerging technology to the marketplace. Several teams worked
with companies in their home states to invent new materials
or products, some of which are awaiting new patents.
Valence Energy, a company comprised of Santa Clara University
alumni who participated in the 2007 contest, helped Team
California design a whole-house control system that can be
operated via an iPhone app, Anand said. Lighting,
entertainment, heating and water systems, even the window
shades all connect to a master computer users can access
remotely.
"They helped make everything talk to each other. So you can
be on the iPhone or the Web site, and you can change the
temperature of your house from the car on the way home," he
said.
Iowa State University's team worked with a firm called
AccuTemp Energy Solutions and with Pella, the window and door
manufacturer, to create a better-insulated door for its
Interlock House.
Timothy Lentz, a mechanical engineering graduate student at
Iowa State, said the door uses vacuum insulation panels to
reach an insulation value of R40 -- the level of a typical
ceiling, and an unheard-of rate for a door.
"This makes it almost a wall," Lentz said.
Incidentally, many homes are so well-sealed that special
ventilation systems also had to be invented. Team Alberta,
comprised of students from four post-secondary schools in the
Canadian province, designed a hot and cold air exhaust system
that saves as much energy as possible. An energy recovery
ventilator, which is basically a box fan covered in a special
material, allows heat transfer between outgoing and incoming
air.
"In old homes, you don't need to worry about mechanical
ventilation because the homes were so leaky. That is not
really true in newer, high-performance homes," said Michael
Gestwick, who is pursuing a master's degree in environmental
design from the University of Calgary. "Our system is highly
integrated, where many other systems that you'll see are kind
of decoupled -- you have one system to do the heating, and
a separate one for the cooling, and a ventilating machine on
top of all that. We took all these pieces and put them
together and wrote control logic to make it work together."
The teams all spent about two years designing, planning and
building their homes. Each house had to be assembled at its
respective university, taken apart to be trucked to
Washington, and re-assembled on the Mall before the
competition began. The houses all feature the latest
energy-efficient appliances and home entertainment systems --
teams must cook, do laundry and host movie night, among other
typical household activities. The 10 categories are meant to
prove that solar homes can not only be cool and efficient,
but comfortable and livable.
Some teams took the latter to heart, knowing many
eco-conscious consumers might not want to live in a house
resembling something out of the Jetsons.
"The other houses, while they are really cool and have all
the bells and whistles, they kind of look like a spaceship.
They wouldn't really fit in areas that we think of, like
mid-size Iowa towns," Lentz said.
The Iowa State house resembles a ranch-style home sliced in
half, with a roof that slants toward the sun. Others took it
even further -- the University of Minnesota and University of
Illinois Urbana-Champaign teams designed homes with
traditional-looking gabled roofs, even opting to sacrifice
energy-collection capacity for the purpose of aesthetics.
Form versus function is always cause for debate in
architecture; Jeff Stein, dean of Boston Architectural
College, part of Team Boston, said the decathlon provides
a new way of thinking about both. He noted that in Western
society, people spend an average of 72 minutes a day outdoors.
"Buildings are hugely important, and they are way more
important than the amount of attention we've been giving them
in the last generation. Now, here comes a different way of
thinking about them, and the solar decathlon is a trigger for
making that (transformation) come into play," he said.
Plus, it will help students find jobs. Lentz, from Iowa
State, said he wants to work in the realm of building and
energy efficiency.
"There is a lot of room for improvement there," he said.
"I've met a lot of people who donated products or services
who keep asking, 'When do you graduate?'"
Aucun commentaire:
Enregistrer un commentaire