The office is becoming a major driver of climate change.

Despite ongoing efforts to improve energy efficiency in the workplace, the world's growing reliance on the Internet is leading to a rapid increase in greenhouse gas emissions.

The energy required to power all the world's computers, data storage, and communications networks is expected to double by 2020, according to a new McKinsey & Company analysis.

The rising emissions are due largely to greater Internet use in China and India, where coal-fired power plants generate the majority of the countries' energy. China accounted for 23 percent of global emissions related to information technology (IT) last year. Worldwide, IT systems' emissions were equivalent to the annual carbon dioxide emissions from more than a half-billion automobiles.

The predicted emission growth comes after years of increased energy demand from the world's computer servers. The amount of electricity required for servers doubled between 2000 and 2005, according to a Stanford University study. The world's 30.3 million servers and other IT systems now account for about 2 percent of global greenhouse gas emissions, the McKinsey report said.

North America's office technology caused one-fourth of the world's IT-related emissions in 2002. China has since passed the region to become the world leader in both overall greenhouse gas emissions and emissions attributed to IT.

China and the world's emerging economies, including India, Brazil, and Indonesia, are expected to increase their IT emissions 9 percent annually in the years ahead. By 2020, McKinsey predicted IT would be the cause of 1.54 gigatons of greenhouse gases, or 3 percent of global emissions. If these calculations are accurate, the carbon footprint of IT would be comparable to that from aviation.

The McKinsey study also noted that the same technology that has increased the workplace's carbon footprint can reduce global emissions. "Smart controls" - sensors that monitor and help avoid unnecessary electricity - are already being installed across the world. "The same way IT improved labor productivity in the ‘80s and ‘90s, IT can improve energy productivity today," said lead author Giulio Boccaletti, a McKinsey consultant.

In order for the emission - and financial - savings to occur, office managers must be willing to pay for the initial efficiency changes. Businesses, however, are often geared toward finding new sources of revenue rather than ways to improve infrastructure.

"Energy efficiency, until very recently, is something people haven't really seen as a fundamental business driver, even though it can create enormous returns," said Boccaletti, a former climate scientist at Massachusetts Institute of Technology.

Many offices and homeowners already appear to be switching to one of the simplest energy-efficiency improvements: compact fluorescent lamps (CFLs). According to a recent Worldwatch Institute analysis, global CFL sales more than tripled from 750 million units in 2001 to 2.4 billion in 2006, based on data from Chinese manufacturers.

Electric lighting consumes 19 percent of the world's electricity grid production. If all the incandescent light bulbs in the United States were replaced with CFLs, the country would avoid 158 million tons of carbon dioxide emissions, according to an industry estimate, the equivalent of removing more than 30 million cars off the road.

Ben Block is a staff writer with the Worldwatch Institute. He can be reached at bblock@worldwatch.org.

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