Wednesday, September 12, 2012 | 6:29 PM
Last year we published Google’s 2010 carbon footprint data for the first time on our Google Green site, and today we’re updating the site with information about our 2011 footprint. We’re also thrilled to report that we’re featured in the Carbon Disclosure Project’s 2012 Carbon Disclosure Leadership Index for a second year.
As we grow our services, we’re doing so in a responsible way. The Internet continues to see explosive growth: we’ve found over 30 trillion unique URLs on the web, up from 1 trillion in 2008. Our servers index 20 billion pages a day, receive 100 billion search queries a month, and support 425 million Gmail users—among many other services. Because we’re carbon neutral, we do all that work with a carbon footprint of zero, minimizing our impact on climate change.
We like to be thorough, so when calculating our carbon footprint we go beyond the typical approach. We cover not only employee business travel, but also daily commuting. We track the miles driven by our self-driving cars and Street View vehicles. And when it comes to our data centers, we take a “kitchen sink” approach—that is, we throw just about everything in. We include data center construction and server manufacturing as well as the energy used by Google-built data centers, leased facilities (called “colos”) and other third-party facilities around the world that house Google equipment.
Our carbon footprint in 2011, before offsetting it, was 1,677,423 metric tons CO2e. As a normal result of continuing to provide more and better services to more users, our energy consumption in 2011 increased in absolute terms, but not in relative terms. In other words, it’s growing less quickly than our business. Our carbon footprint per million dollars of revenue—a measure of carbon intensity commonly used to track corporate sustainability—has decreased by an average of 10% each year since 2009.
Our data centers hit a new low this year—in a good way. The average power usage effectiveness (PUE) across our global fleet of data centers has dropped to our lowest (AKA best) yet: 1.13 (with some facilities dipping as low as 1.08 earlier this year). This means we’ve managed to reduce the amount of energy we use on cooling and other overhead to just 13%.
Our campus sustainability programs are thriving. Last year, our shuttle program saw a 60% increase in ridership, and Googlers drove our fleet of hybrid and electric vehicles over 220,000 miles. The combination of our employee shuttle system and our electric vehicle infrastructure takes the equivalent of about 3,000 cars off the road every year. And we’re proud to have over 6 million square feet of building space around the world set to achieve LEED certification.
We continue to look for and implement new ways to reduce our impact on the environment while we increase our impact on sustainability, green energy, and clean technologies. We look forward to reporting back next year on our latest numbers, innovations, and activities.