8 oct 08 | Building (online)

Sears tower set for green makeover

By Phil Clark

Chicago landmark skyscraper plans to install wind turbines and PV to reduce energy use by 10%.

Chicago's Sears tower, the world's tallest skyscraper when it was built in 1973, is due to receive a green makeover to reduce energy use by 10%.

The scheme, which is at planning stage, is being overseen by US practice Adrian Smith + Gordon Gill Architecture. Speaking at this week's Cityscape conference partner Adrian Smith said the project would use PV and wind turbines on the roof as well as incorporating new lighting systems, extra insulation and a green roof. For more detail on this scheme see the video below.

Asked if the energy reduction planned was relatively low Smith said energy had already been reduced in the building since it was completed. "They've already reduced the energy consumption by 50% between then and now," he said.

Former London mayor Ken Livingstone, who was chairing the conference, said since the Greater London Authority had started a program of retrofitting public buildings such as fire stations they had seen a 25% drop in energy. He said: "It was more than we expected."

In his talk on sustainable skyscrapers Smith claimed that the world's current tallest building, the Burj Dubai, had "sustainable features" in that "its form and systems respond optimally in the environment" and that it was built on a brownfield site and would benefit from district cooling.

Smith said one potential idea his firm was "examining" was whether it could transport cold air from the top of the Burj Dubai to the bottom. On a recent visit he recorded a difference in temperature from the bottom to the top of the tower of 10 degrees centigrade.