Clearly, it's a thorny issue. But that's just one side of the coin.

A survey by Pike Research adds to the debate as to whether Cloud computing is a 'greener' approach to running data centres. It indicates that the energy savings of Cloud computing are 'substantial'.

In its report, Cloud Computing Energy Efficiency, the market intelligence firm claimed that the adoption of Cloud computing would lead to a 38 per cent reduction in worldwide data centre energy expenditures by 2020.

As part of its Cloud computing adoption scenario, Pike Research forecasts that data centres will consume 139.8 terawatt hours (TWh) of electricity in 2020, a reduction of 31 per cent from 201.8 TWh in 2010. The reduction will drive total data centre energy expenditures down from $23.3 billion in 2010 to $16.0 billion in 2020, as well as causing a 28 per cent reduction in greenhouse gas emissions from 2010 levels.

According to Pike Research, the report shows computing Clouds are able to achieve industry-leading rates of efficiency. It highlights the fact that only the largest of organisations would have the financial resources to offer the same levels of efficiency within their own data centres.