Second-tallest building in the world nearly finished

The world's second-tallest building, due to be completed next year, was highlighted in a topping-out ceremony on Saturday to celebrate the final beam put in place.

The Shanghai Tower soars to 125 floors and 2,073 feet, topped only by the Burj Khalifa in Dubai. The $2.2 billion giant joins the Shanghai World Center and the Jin Mao Tower as a trio of supertall buildings making up the heart of the city's financial district.

Shanghai Tower is built with a rounded design that reduces wind load on the building and 25 percent less structural steel than a conventional design, which is expected to save $58 million off the cost of the construction. The tower will boast wind turbines near its top which will generate some of its energy and the building's heating and cooling will run on geothermal energy sources.

Construction broke ground on the tower at the end of 2008, and the overall completion is expected next year.

Its place as second-tallest will be short lived, however, as the Sky City One skyscraper in Hunan, China, is set to take over as the tallest building in the world in April 2014.

Built by U.S. architect firm Gensler, the Shanghai Tower is owned by Shanghai Chengtou Holding, Shanghai Lujiazui Finance & Trade Zone Development and Shanghai Construction Group.