How much can energy efficiency save a business? Ask IBM, which says its conservation programs have cut its bills by more than $50 million in electricity costs since 2008. The amount of electricity it’s saved is enough to power 47,000 average US homes for a year.

Currently celebrating its 100th anniversary, IBM has run 3,100 conservation projects at more than 350 facilities in 49 countries. Its goal is to eliminate 1.1 million megawatt-hours of energy consumption by the end of 2012.

The company’s strategies include a technology developed by IBM Research that produces real-time, 3D images to pinpoint so-called “heat sinks” and cooling leaks. It also uses virtualization technology to help energy-hungry servers operate at peak efficiency and analytics software to manage electricity consumption across data centers.

According to its latest Corporate Responsibility Report, IBM also recycled 79 percent of the nonhazardous waste it generated in 2010 and successfully completed a multi-year program to eliminate perfluorooctane sulfonate and perfluorooctanoic acid compounds from its chip manufacturing processes.

Over the years, the company estimates that its environmental efforts have avoided costs at a rate of approximately $1.60 for every $1.00 spent.

“Saving millions in electricity expenses takes more than turning off lights,” said Wayne Balta, vice president of environmental affairs and product safety at IBM. “It takes the combined efforts of IBM experts working in data center operation, manufacturing, hardware, software, R&D and real estate management. It also includes a combination of analytics technology and integrated management systems to find patterns and trends in energy consumption to improve efficiency.”

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