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Meeting the hidden cost of IT

By combining energy efficiency measures and renewable energy sources, data centres could reduce energy consumption by 30-40 %. Image: Shutterstock/  kubais
By combining energy efficiency measures and renewable energy sources, data centres could reduce energy consumption by 30-40 %. Image: Shutterstock/ kubais

Almost 50 000 Google searches per second, 3 billion internet users, 500 million tweets per day – the data centres that underpin our information age now use 2 % of Europe's energy, researchers say. That’s the same as the energy used globally by the aviation industry.

And it’s rising fast, as more and more people use their smartphones to do their shopping, hail taxis, meet friends and read their daily newspapers.

‘Data centres are very open to analysing options and solutions because they know that energy costs will increase in the future and are increasing now,’ said Dr Jaume Salom, whose EU-funded RenewIT project is helping tech firms to envisage how much energy saving techniques can help them.

The more efficient that data centres become, the greater proportion of their energy can be sourced from renewable sources such as solar power and wind.

‘Our vision is that before applying any kind of renewable you have to make an effort to reduce your energy consumption as much as possible,’ Dr Salom said. ‘Once you have decreased your energy consumption you are in a good position to apply renewables.’

‘Energy costs will increase in the future and are increasing now.’

Dr Jaume Salom, coordinator, RenewIT

The project is developing a tool that allows data centres to estimate the impact of using different energy efficient measures and renewable energy sources in advance of putting these measures into place. It is being tested at eight data centres across Europe. 'The tools will focus redesign of data centres,' said Dr Salom.

One idea, known as free cooling, replaces the data centre’s cooling system with outside air in the winter. It’s already used in large data centres, but is uncommon in smaller ones. Such systems can work particularly well in areas of Europe that experience extremely cold winters, providing significant annual energy reductions.

Dr Salom hopes that by combining energy efficiency measures and renewable energy sources data centres can reduce their primary energy consumption by 30-40 %.

Communities could save money if the hot water from the data centre’s cooling system was pumped into the local heating system, providing hot water for nearby residents.

It’s a solution developed by the EU’s GreenDataNet project, which is investigating ways that data centres in urban environments can integrate with the surrounding infrastructure to make the whole system more efficient.


But changing the way the data centres themselves function could have a major impact on the amount of energy they use. The idea is that instead of having one or two large servers per rack unit, you have tens of smaller much less powerful servers, known as microservers.

These banks of microservers are more flexible, which improves their energy efficiency. The microservers in a rack unit can be switched on and off as required by the workload, reducing and increasing power consumption as necessary; while one large server has to run all the time.

The blueprints for rack units that can include microservers have already been drawn up by the EU-funded CoolEmAll project in partnership with Christmann, a German IT company.

The blueprints are now available for other people to download and use, and Christmann is now working on their own versions for the mass market.

Although implementing some of these solutions can be expensive, with electricity costs accounting for over 10 % of the running cost of a data centre according to data expert Professor Jonathan Koomey at Stanford University in the US, they can reduce costs in the long term helping European businesses to become more competitive. 

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