The energy savings that Verizon Wireless reaped from deploying thin clients and power-management software at its call centers were both dramatic and immediate -- so much so that during initial testing at the company's Chandler, Ariz., call center, the local power utility called to find out if it had moved. All told, the effort has yielded a 50 percent drop in energy consumption.

As with many green IT initiatives, Verizon's transition to energy-sipping thin clients resulted from several considerations, including the need to increase operating efficiencies and cut costs. "Users tend to move from desktop to desktop at our call centers, so thin clients made a lot of sense, since they could take all their profiles and desktop look and feel with them," says Mike Bowman, Verizon's associate director of planning and engineering. "We were also looking to lengthen meantime between failures and reduce power consumption and the volume of material we dispose of each year. Thin clients are about the size of a normal telephone handset."

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Bowman also points out that Verizon Wireless expects to get five to eight years out of its thin clients, opposed to the three years for a typical PC.

Verizon Wireless has transitioned to thin clients in 17 call centers, adopting Sun Ray thin clients at five and HP thin clients and Citrix technology at the remaining twelve. The energy conservation benefit has not only come through lower thin-client power consumption -- Sun Ray clients, for example, draws only 4 watts of electricity each, compared to 55 to 80 watts or so for a PC -- but also reduced cooling needs. "PCs throw off a lot more heat than thin clients, so we've seen definite reductions in cooling costs at our call centers as well," Bowman says.

Other benefits have included reduced administrative costs, since most updates are done at the server, rather than distributed across thousands of PCs. Verizon Wireless has also seen a 60 to 70 percent drop in desktop problems and an improvement in business continuity, as Verizon Wireless can keep more desktops running on backup power during a power outage.

The principal challenge was simply getting all of Verizon Wireless's software to work in a thin-client environment. "We had to work with the development teams to change some code and get some third-party drivers that could run the on thin clients," Bowman says.

Verizon hasn't abandoned PCs entirely -- but the company has cut its energy consumption by 24 percent using two PC power-management products from 1E: Night Watchman and 1E Wakeup. Verizon used to leave PCs on overnight for patching. Now, Night Watchman shuts down systems automatically across several time zones after working hours based on a centrally configured schedule; 1E Wakeup turns them on again for late-night patching or a half-hour before the next shift. "We've saved $1.3 million over that past 12 months across 55,000 desktop PCs," Bowman says.

Now Verizon Wireless is looking to implement similar measures at other facilities. "There's a new awareness of green technologies that wasn't there before," Bowman says. "We're looking to see how we can implement these ideas at our retail locations and take all of this a lot further."