At the Dallas/Fort Worth 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, DC, 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,” says 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, like ”green roofs,” where a layer of plants on a roof helps the building retain heat in winter and stay cool in summer, and new ideas, like special coating for windows that let’s 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 United States Green Building Council launched a programme to accredit building professionals in environmental design. Interest in the programme, called Leed, for Leadership in Energy and Environmental Design, has skyrocketed. Since 2000, about 19 000 people have been accredited, 9 000 in the last month alone.
About 4% of new commercial construction is now completed under Leed guidelines, said Taryn Holowka, a spokesperson 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 US was formerly 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.
More sophisticated building materials are in development.
Architect Stephen Kieran’s firm is working on ”smart wrap” that 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% have energy management systems or time clocks that turn lights on or off based on the time of day, he said.
Interest in smart, energy-efficient buildings is growing, especially among those who manage large facilities, 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 7C sea water and the condensation on the pipes will be used for irrigation.
New systems use energy when it’s cheapest.
The Dallas/Fort Worth Airport installed a 22,8-million-litre 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% during periods of peak electrical demand.
”This saves real money while we use less resources and pollute less,” said Jim Crites, executive vice-president of operations at the airport.
Gray water systems, which recycle water from sinks and showers, were once largely the province of hippies.
But President George Bush’s ranch in Crawford, Texas, has such systems, as will The Bank of America Tower at One Bryant Park in New York, a 54-storey building being developed by the Durst Organisation. – Sapa-AP