Green data centre concerns vs. high-tech IT infrastructure

As data centre infrastructure continues to grow, Jeff Thomas, chief executive of Ark Continuity, discusses green data centre options, including ideas to reduce energy consumption and CO2 emissions.

The U.K. is committed to creating a low-carbon economy, rightly seeking to reduce energy consumption and carbon emissions whilst employing alternative and renewable sources of energy.

However, while the information society continues to boom and Britain strives to compete as a world leader in the knowledge-based economy, balancing the need for high-tech infrastructure against environmental concerns will remain a challenge.

The role of ICT is set to grow. This will result in an exponential growth in infrastructure with a rise in energy consumption and CO2 emissions, at a time when power brown and blackouts are predicted.

How can we balance these opposing drivers?
The Greening Government ICT strategy aims to take a lead by making energy consumption of Government ICT systems carbon-neutral by 2012, and making them carbon-neutral across their lifetime by 2020. Green data centres play a key role in achieving this target.

According to IDC, the number of servers worldwide is set to increase by almost 18% per annum until 2020 -- an increase from 18 million in 2008 to 122 million. The percentage of those servers located in data centres rather than in server rooms' on-site will increase rapidly. With demand for space high and supply still low, particularly in U.K., selecting green data centre space is one of the most important decisions IT procurers will make.

Investment in IT should be made in such a way as to reduce greenhouse gas emissions. When purchasing data centre capacity, there are three key data centre concerns to consider.


  1. The carbon footprint of the facility (design, build and operation).
  2. Increasing the efficiency of processes, reducing energy consumption and sourcing of energy (renewable sources).
  3. The management of waste data centre energy.


Caution is required on the second point. Data centre electrical load profiles are generally not compatible with on-site renewable power generation, so offsite mitigation may be considered as an alternative. The key driver in reducing the carbon footprint is the consumption of energy over the life of the facility.

Selecting data centre space is one of the most important decisions IT procurers will make.



 The power usage effectiveness (PUE) is the ratio of power entering the facility compared with power used by the IT kit inside. PUE is used as a guide to the effectiveness of a specific data centre. The closer the PUE is to 1, the higher the efficiency of the system, although a PUE of exactly 1 cannot be achieved. Older data centres tend to run at a PUE of 3 and above. The U.K. industry average is 2:2.

While PUE is a useful starting point, there are other sustainability measures that need to be considered.

Data centres have generators as backup for electricity supply failures. Most use battery-based uninterruptible power supplies (UPSes) to deliver power while the generators start up. These batteries require conditioned environments that consume significant energy. In addition, the batteries have a relatively short life and usually end up in a landfill. The more sustainable option is to use a kinetic UPS system that provides a source of autonomous power, removing the need for batteries in the UPS.

The key to determining whether a data centre developer is really going to deliver a sustainable option is ensuring that it has been built "from the ground up." Sustainability must not be treated as an afterthought and seen as the expensive option. Real sustainability will result in a significant reduction in the carbon footprint and will help reduce costs by increasing data centre energy efficiency. It is therefore important to select a data centre provider that embraces data centre best practices and sustainable principles in the design, construction, engineering, operation and end of life of their data centres.

Jeff Thomas is the chief executive of Ark Continuity and a contributor to Ark Continuity is a vendor-independent outsourcing data centre organisation that is currently unveiling a new campus at Spring Park, Corsham, Wiltshire.

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