Sears (now Willis) Tower a Giant Example of Green Building at Its Best

Solar panels, windmills, a green roof, and 16,000 replacement windows. That’s the recipe for refurbishment that the former Sears Tower in Chicago is cooking up to become a towering model of efficient office space.

Here’s a breakdown of what’s taking place. Highlights include:

• Efficiency improvements to the building’s exterior envelope and windows. The tower has 16,000 single-pane windows. Sustainability plans for the building call for a window replacement and glazing program. Strategies to achieve a thermal break of the curtain wall are also being investigated. These upgrades would achieve savings of up to 50 percent of heating energy.
• Mechanical systems upgrades in the form of new gas boilers that utilize fuel cell technologies, which generate electricity, heating and cooling at as much as 90 percent efficiency. Mechanical upgrades also will include new high-efficiency chillers and upgrades to the distribution system.
• The tower’s 104 high speed elevators and 15 escalators that will be modernized with the latest technology to achieve 40 percent reduction in their energy consumption.
• Water savings that will be realized with conservation initiatives through upgrades to restroom fixtures, condensation recovery systems and water efficient landscaping,which will reduce water usage by 40 percent and save 24 million gallons of water each year.