The carbon footprint of IT equipment is growing twice as fast as the contribution that IT makes to economic productivity, according to a study by scientists in Singapore and the US.

The study estimated the energy consumption and projected adoption of various types of IT equipment – data centres, PCs, mobile devices, games consoles. Interestingly, while the energy consumption of PCs and data centres is roughly equivalent today, the authors expect PC energy consumption to grow much faster between 2015 and 2020.

Source: University of Houston / Rice University

The researchers correlated these numbers with the projected contribution that the IT sector will make to the gross domestic product of the US from 2009 until 2020. In 2009, the IT sector created $2.8 for every kilogram of CO2 it burned, the study found. In 2020, that figure will fall to just $1.1 per kilogram. In other words, the economic reward for producing CO2 to power IT equipment will half in the next decade.

There are a few problems with the study. As the authors themselves concede, there are a great number of assumptions and estimates built into their calculations. And, like most attempts to evaluate the economic contribution of IT, they do not include the efficiency improvements that IT makes to business operations.

Thirdly, it is not possible to extrapolate the GDP contribution that IT makes to the US economy – where much of the software industry is based, for example – to the rest of the world.

Nevertheless, it presents a way to think about the carbon footprint of the IT sector relative to its economic contribution that may instruct carbon policy and innovation investment.