Having been surpassed by the Burj Khalifa on virtually every level, the world's second tallest building, Taipei 101, needed something to set it apart. Enter the Green On campaign, an effort to conserve energy and promote recycling in the building. Their efforts were made official on July 28, 2011, when the 1,670-ft. (509 m) skyscraper received LEED Platinum Certification. The honor, bestowed by the U.S. Green Building Council, validates Taipei 101 as the tallest green building in the world — and again gives the tower something to boast about. As a result of the initiative, which includes a water-recycling system on the roof, the building's energy consumption is reportedly some 30% lower than that of an average building of its size.