Willis Tower Becomes Largest Office Building To Earn Energy Star Certification

by | Feb 12, 2018

Willis Tower Chicago Energy Star

Credit: Willis Tower file photo

Chicago’s iconic Willis Tower has earned Energy Star certification, becoming the largest office building and the third largest building overall to have the designation, according to property manager Equity Office.

Willis Tower, previously known as the Sears Tower, was originally constructed in 1973. Owned by the Blackstone Group, the building is 110 stories tall and has more than 4.5 million square feet of space. Currently more than 100 businesses are located within the tower. Skydeck Chicago on the 103rd floor is the country’s highest observation deck.

Equity Office says that Willis Tower improved its energy performance by managing energy strategically across the entire organization and by making cost-effective improvements to the building.

Infrastructure retrofits and energy management practices included:

  • Retrofitting HVAC, which included solar window filming, air infiltration points, and exterior air damper banks
  • Adding motion sensors in all mechanical areas and some common areas
  • Adding lighting control panels in tenant areas to help reduce lighting operation in areas not in use
  • Retrofitting lighting to high efficiency LED fixtures and lamps in building common areas, main lobbies, mechanical floors, and elevator cabs
  • A building-wide upgrade of the building automation system for more efficient temperature control, HVAC sequencing, and energy monitoring to allow for demand response opportunities.
  • Replacing antiquated variable frequency drives and installing new VFD drives on equipment that communicate with the BAS so managers can ID opportunities for energy conservation
  • Modernizing around half the building’s chillers
  • Retrofitting all the cooling towers

Earning Energy Star certification for a commercial building means that Willis Tower uses an average of 35% less energy than a typical building, and that it releases 35% less CO2.

The 2017 National Green Building Adoption Index released last July found that Chicago had the most building spaces with LEED and Energy Star certification in the United States among the country’s 30 largest real estate markets.

“Green buildings are getting the bigger tenants, higher dollars, and more investor capital,” David Pogue, global director of corporate responsibility for CBRE, told Bloomberg Markets at the time.

The 3rd Annual Environmental Leader & Energy Manager Conference takes place May 15 – 17, 2018 in Denver. Learn more here.

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