2 of 5
Money saved: $5.7 million per year
Fortune 500 rank: 11

2010 was a big green year for HP, which made an $11 million investment in energy efficiency improvements. HP expects big returns from the project, which should shave off 70 million kilowatt hours every year, generating an estimated savings of $5.7 million annually.

Energy savings is only one part of the big tech company's three-pronged environmental strategy: One tier focuses on how the company can cut costs internally, the second targets how to help other companies run with greater energy efficiency, and the third aims to help consumers. HP wants to not only launch energy-efficient products, but educate people about how to use them with the lowest possible carbon footprint.

Like many tech companies, HP is internally trying to minimize the energy drained at its data centers. They've started that effort by first shedding unnecessary facilities. Last year, the company closed down 16 data centers as well as 447 computer labs. These and other changes helped trim HP's greenhouse gas emissions by over 9% in 2010, which puts it on track to reach its goal of a 20% reduction in greenhouse gas emissions, based off of 2005 levels, by the year 2013.

NEXT: International Business Machines
Last updated May 16 2011: 6:18 PM ET
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