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Buildings conserve energy, money
Web Posted: 10/31/2004 12:00
AM CDT
Ellen Simon
Associated Press
At Dallas-Fort Worth International Airport, the lights are controlled
by sensors that measure sunlight. They dim immediately when it's
sunny and brighten when a passing cloud blocks the sun.
At a new middle school in Washington, D.C., the air conditioner
shuts off when a window is open.
A wall of windows at a University of Pennsylvania engineering building
has built-in blinds adjusted by a computer program that tracks the
sun's path.
Buildings are getting smarter — and the next generation of building
materials is expected to do even more.
Windows could trap the sun's energy to heat hot water. Sensors that
measure the carbon dioxide exhaled by people in a room could determine
whether the air conditioning needs to be turned up.
"More potential products have been invented in the last 15
years than in the entire prior history of architecture," said
Philadelphia architect Stephen Kieran. "We're only beginning
to tap the potential of those materials."
The new materials and technology are being used in a wave of buildings
designed to save as much energy as possible. They range from old
ideas, such as "green roofs," in which a layer of plants
on a roof helps a building retain heat in winter and stay cool in
summer, and new ideas, such as special coating for windows that
lets light in but keeps heat out.
Most commercial buildings in the United States still lack the most
rudimentary technology, such as timers for lights, but the idea
of buildings that use technology to save energy got a boost from
the 2000 energy crisis, when California experienced blackouts and
electricity prices rose.
That year, the U.S. Green Building Council launched a program to
accredit building professionals in environmental design. Interest
in the program, called LEED, for Leadership in Energy and Environmental
Design, has skyrocketed. Since 2000, about 19,000 people have been
accredited, 9,000 in the past month alone.
About 4 percent of new commercial construction is now completed
under LEED guidelines, said Taryn Holowka, a spokeswoman for the
Green Building Council.
Many new building materials are first developed in Europe, where
energy is more expensive.
"The construction industry is behind the times in some ways,
compared to many other industries," said Patrick Mays, chief
information officer of architecture firm NBBJ.
Smart-building technology in the United States used to be reserved
for large projects and college campuses.
"Now we're seeing it make its way down, even to the residential
market," said Jim Jones, an architecture professor at Virginia
Tech. Think of the motion-sensing lights common outside garages
and front doors.
As technologies such as sensors become cheaper, their uses spread.
The elevators at Seven World Trade Center, which is under construction
at New York's ground zero, have a dispatch system that groups people
traveling to nearby floors into the same elevator, thereby saving
elevator stops and trips. People who work in the building will enter
it by swiping ID cards that will tell the elevators their floor;
readouts will then tell them which elevator to use.
The building also has windows with a coating that blocks heat while
letting in light.
More sophisticated building materials are in development.
Architect Stephen Kieran's firm is working on "smart wrap,"
which uses tiny solar collectors to trap the sun's energy and transmitters
the width of a human hair to move it.
"The materials in smart wrap are either commercially available
or they've been developed in corporate or university research labs,"
said Kieran, a partner at Kieran Timberlake in Philadelphia. "They're
poised to change the face of the construction industry in the next
decade or so."
Still, relatively cheap energy costs in the United States mean most
building owners remain unconcerned with efficiency, said Srinivas
Katipamula, a research engineer at Pacific Northwest National Laboratory.
Of the roughly 4.7 million commercial buildings in the United States,
only 10 percent have energy management systems or time clocks that
turn lights on or off based on the time of day, Katipamula said.
Carlton Brown, chief operating officer of building developer Full
Spectrum, is finishing a smart, green 128-unit condo project in
New York's Harlem neighborhood that took more than five years to
get off the ground.
"We were talking about a
green building and a smart building, and people were not really
interested," he said.
Full Spectrum is finishing the project, which includes wireless
broadband in every unit and washing machines that can be reserved
via the Internet.
Interest in smart, energy-efficient buildings is growing, especially
among those who manage large sites, such as airports, and buildings
that traditionally use lots of energy, such as laboratories.
That's because "the operating costs of a building in its lifetime
can be hundreds of times more expensive than the building was in
the first place," said Doug Lockhart, who until recently worked
as energy manager for Lawrence Berkeley National Laboratory.
A new building at the Natural Energy Laboratory of Hawaii will be
a "net zero energy building," using no energy from the
electric grid. The building will be cooled with piped-in 43-degree
seawater, and the condensation on the pipes will be used for irrigation.
New systems use energy when it's cheapest.
D-FW Airport installed a 6-million-gallon thermal storage tank that
lets the airport chill air conditioner coolant in the middle of
the night, when energy is cheapest, for use during the day, when
energy is more expensive. This has cut cooling costs by 91 percent
during periods of peak electrical demand.
"This saves real money while we use less resources and pollute
less," said Jim Crites, the airport's executive vice president
of operations.
Gray water systems, which recycle water from sinks and showers,
were once largely the province of hippies.
But President Bush's ranch in Crawford has such systems, as will
the Bank of America Tower at One Bryant Park in New York, a 54-story
building being developed by the Durst Organization.
Douglas and Jody Durst, co-presidents of the company, said they
became interested in environmentally conscious building when they
worked on energy-saving retrofits to their older buildings during
the 1970s.
"We realized there was a better way to build them from the
start," Douglas Durst said.
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