Cloud energy consumption estimates challenged by study


The energy costs associated with relying on consumer cloud services may not be as high as previously thought, it has been claimed.

The Centre for Energy Efficient Telecommunications (CEET) published a report earlier this year, which claimed the amount of energy consumed by wireless clouds will quadruple over the next three years.

Its Power of the Wireless Cloud report also claimed the amount of energy used to access networks exceeds the amount consumed by datacentres by a “significant” margin.

This point has been contested, following the release of new findings by two members of the ESP KTN technology community: Professor Paul Krause and Memset managing director Kate Craig-Wood.

The pair investigated the energy costs associated with cloud-based transactions, such as streaming a film or downloading an album from iTunes.

“Previous research suggested that in the public cloud, end user access over wireless networks uses ten times as much energy as the datacentre,” read the statement released to publicise the research.

“But a key finding of this new research revealed that the energy consumed in networks is utterly inconsequential to the energy consumed at the datacentre the home (for general cloud services).”

In fact, the pair claim people’s online activities account for just 0.5 per cent of our total energy footprint, and described this as an “inconsequential figure” given the benefits being connected to the web afford us.

“Putting this into perspective when looking at our daily carbon usage, the average home broadband usage is 23GB/month, which becomes 2,000 Wh/day based on the laptop user model,” the statement read.

“The average Briton consumes 195,000 Wh/day of energy and there are on average 2.3 people per household, so online activities account for perhaps 0.5 per cent of our total energy footprint.”

The research forms part of the Memset MD’s PhD study into the relationship between cloud computing and climate change, and should go some way to disproving the notion that IT is environmentally unfriendly, she claims.

“A typical Briton spends perhaps 0.5 per cent of their daily energy consumption on internet services, including everything from the data centre to the laptop,” Craig-Wood explained.

“Given that ICT is expected to save 16 per cent of societal emissions by 2020 and the sector already contributes 10 per cent to GDP, the climate impact of our industry is clearly not a significant concern at this stage."

Professor Krause said the research yields a figure of 1592 Wh/GB for the energy consumed while transferring data from a regional datacentre to an end user, based on the average British bandwidth use being 23 GB per month.

“This is significantly lower than earlier published estimates, but this difference can be accounted for by efficiency gains over the last seven years,” said Krause.

“It is possible that these efficiency gains are being countered by increased resource consumption. However, these additional internet mediated activities often replace other activities with significantly higher energy budgets,” he concluded.

Caroline Donnelly is the news and analysis editor of IT Pro and its sister site Cloud Pro, and covers general news, as well as the storage, security, public sector, cloud and Microsoft beats. Caroline has been a member of the IT Pro/Cloud Pro team since March 2012, and has previously worked as a reporter at several B2B publications, including UK channel magazine CRN, and as features writer for local weekly newspaper, The Slough and Windsor Observer. She studied Medical Biochemistry at the University of Leicester and completed a Postgraduate Diploma in Magazine Journalism at PMA Training in 2006.