Switching the communications company’s air systems to “economizer mode” allows cool external air to replace mechanically chilled air during cool months, saving energy and money, AT&T says.
The project was part of the EDF Climate Corps fellowship, which places specially trained students from business schools with host companies to build the business case for energy efficiency.
AT&T first participated in the program in 2010, identifying a potential 80 percent savings on lighting costs across 100 million square feet of AT&T real estate. The company is now in the process of installing lighting sensors at nearly 250 locations.
Over the summer the Climate Corps fellowship helped McDonald’s, Target and 76 other organizations make $650 million in savings and 440,000 annual metric tons of CO2 reductions, it was revealed in September.
The Corps is now in its fourth year, and projects accounting for 86 percent of the energy savings identified by 2008-2010 fellows are complete or underway, EDF says.
Earlier this month, it emerged that economizers such as those highlighted in the AT&T study are now used in almost half of data centers.
Green Grid’s survey said that data centers using such technology are saving an average of 20 percent on energy costs.