The Reichstag, Germany’s parliament building, was retrofitted in 1999 with a new dome that uses glass and mirrors to reflect daylight deep into the main chamber, reducing dependence on artificial lighting. It also employs a funnel to divert and collect rainwater.
Designed by British architect Norman Foster, the renovated Reichstag has become a Berlin tourist attraction and an energy saver.
The dome-reflector system also draws warm air out of the building. This feature, combined with the fact that the building can make its own electricity from refined vegetable oil, as well as store excess heat underground, brings the building’s carbon dioxide (CO2) emissions down by 94 percent, according to the architect.
Green buildings have myriad benefits, including reductions in greenhouse gas emissions, water use, and toxic materials use, improved air and water quality, and relief from the heat.
In the U.S. there is a debate brewing on Capitol Hill about how to define a green building.
The U.S. government requires all new federal construction to follow the U.S. Green Building Council’s (USGBC) requirements for a gold rating.
USGBC ratings—certified, silver, gold, and platinum—are awarded based on several factors, including sustainable site development, water savings, energy efficiency, and materials selection.
But, to the disappointment of some chemical and plastics companies, the USGBC’s rating system is expected to change next year and may discourage builders from using some products such as PVC piping. A coalition of chemical and plastics manufacturers is lobbying Congress to use another set of criteria.
(See how the U.S. government has gone green in National Geographic News’ “Pictures: Seven Supergreen U.S. Government Buildings.”)