Cities worldwide are promoting environmentally "green' roofs to mitigate several urban problems. Ground cover, shrubs and other flora planted across a building's roof can reduce storm water runoff, easing the burden on local sewers and water treatment systems. And the vegetation can keep the roof cooler in summer, lowering interior air-conditioning costs and therefore peak demand on area power plants.
Links:
[1] http://admin.indiaenvironmentportal.org.in/feature-article/living-cover
[2] http://admin.indiaenvironmentportal.org.in/category/author/mark-fischetti
[3] http://admin.indiaenvironmentportal.org.in/category/journal/scientific-american
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/energy-efficiency
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/green-buildings
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/green-spaces
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/united-states-america-us
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/sustainable-development