The group says that while Facebook, Google and Yahoo are leading the way in making the technology greener, the others were powering their clouds with dirty energy, including coal and nuclear power.
In a report, with the catchy title How Clean is Your Cloud?, Greenpeace said that three of the largest Internet technology companies, Amazon, Apple and Microsoft, were rapidly expanding without adequate regard to source of electricity.
The environmental group said there was a split within the high-tech industry between companies taking steps to power their clouds with clean energy.
Yahoo and Google were leaders in making access to renewable energy in their expansion of cloud technology. Greenpeace liked Facebook for constructing its latest data centre, in Sweden, that can be fully powered by renewable energy.
Google says, through renewable energy purchases and investments, carbon offsets and on-site green initiatives, the Internet giant has been claiming that it has been carbon neutral since 2007.
Greenpeace suggested Amazon’s cloud technology has relied on coal for a third of its juice and nuclear power for another third.
It gave the company a grade of ‘F’ for energy transparency, renewable energy and green advocacy.
Amazon told Canada.com that cloud computing is inherently more environmentally friendly than traditional computing.
The spokesman said that the report’s data and assumptions about Amazon were inaccurate because the company combines hundreds of thousands of Amazon partners into a handful of data centres in the company’s cloud. This makes for a combined smaller carbon footprint that significantly reduces overall consumption.
Apple relied upon coal for just over half of its electricity and nuclear power nearly a third.
Microsoft uses 39.3 per cent coal and 26 per cent nuclear power for its cloud technology.
Twitter used about 35.6 per cent coal technology and 12.8 per cent nuclear energy to power its cloud.
Unlike the others, a spokeswoman for Twitter, said the report raised important considerations around energy efficiency. She said that Twitter would try to do better as it builds out its infrastructure.