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Swiss Re Tower is a typical example of green architecture in London, and what is most remarkable about this building is its energy-efficiency. Thanks to its artful design and some fancy technology, it is expected to consume up to 50% less energy than a comparable conventional office building. Green architecture is changing the way building are designed, built and run.
Green architecture, a term which only came into use in the 1990s, has its origins in the energy crisis of the 1970s, when architects began to question the wisdom of building enclosed glass-and-steel boxes that required massive heating and cooling systems.
The forward-looking architects began to explore designs that focused on the long-term environmental impact of maintaining and operating a building. This approach has since been formalized in a number of assessment and rating systems, such as the BREEAM standard introduced in Britain in 1990, and the LEED standard developed by the United States Green Building Council starting in 2000.
Going green saves money by reducing long-term energy costs; a survey of 99 green buildings in America found that on average, they use 30% less energy than comparably conventional buildings.
Green buildings can also have other benefits. The use of natural daylight in office buildings, for example, as well as reducing energy costs, also seems to make workers more productive. Lockheed Martin, an aerospace(航空宇宙) firm, found that absenteeism(旷工) fell by 15% after it moved 2500 employees into a new green building in Sunnyvale, California. Owing to its delicate design and advanced technology, Swiss Re Tower in London uses less energy than those traditional office buildings by______.