Microsoft has invested in a 2012 study that found small- and medium-sized businesses can significantly reduce their carbon footprint by taking advantage of public cloud computing providers.
2011 and 2012 produced many studies similar to this one, showing how cloud computing is green. Because they were typically sponsored by cloud computing providers, they are less than objective.
The National Data Center Energy Efficiency Information Program’s factsheet states that the amount of energy consumed by data centers is set to continue to grow by 12% per year. In the last 5 years, data centers have been built at a high rate. While they are, indeed, much more energy efficient, they all consume huge amounts of power.
The problem is that businesses and government are still growing their IT infrastructure and need data centers to house that infrastructure. Thus, they have been silently building data centers to support the growth. At the same time, the growth of cloud computing has driven many of the larger providers, such as Google, Microsoft, Amazon, and even Apple, to build additional data center space as well.
The reality is that things will get worse before they get better. Public cloud computing has been an option for the last several years, although most enterprises and government agencies have not yet migrated a significant number of systems to the cloud. At the same time, cloud providers are building to prepare for the forthcoming migration.
At some point, we should see more use of public cloud computing services, thus better sharing of resources, and thus the reduction of data centers and the power that they require. However, my sense is that it will be later rather than sooner. Until then, increases in the carbon footprint will be partly driven by the growth of cloud computing, despite its wide availability.