While our exit from the European union is very much in the news, our shared purpose and collaboration with our neighbours isn’t so widely celebrated. John Booth MBCS, Vice Chair of the Green IT SG and Managing Director of Carbon3IT, looks at energy hungry data centres and explains how (and why) the green tide is turning.

Data centres are the beating heart of all digital transactions that we carry out. Emailing? You’ll be going through a couple of data centres. Buying something online? Data centres. Taking money out from an ATM? Data centres. On social media? Data centres. Even driving and using a sat-nav... yes, you’ve guessed it... data centres. And yet these facilities that can range from a small cell tower base-station to a large hyperscale cloud data centre are largely unknown to the public.

Digital heart

Over the last few years, to satisfy our digital craving (social media, 4G and the like) and even more so during the COVID-19 pandemic (where data centres have proved to be a lifeline for many individuals and businesses), many new ones providing cloud services are springing up all around the globe. It is estimated that there are 450 large hyperscale (cloud) data centres in operation and 150 plus under construction right now - and far more ‘edge’ sites.

Edge is a concept that requires data to be processed where it is created, so small data centres are built at the ‘edge’, to provide processing for 5G, IoT, AI and autonomous (self-driving vehicles). The industry is running flat out to provide homes for all the equipment needed to satisfy our digital needs, but all is not well.

Sustainability and energy consumption

It is important to split a data centre into two elements: the building itself and the ICT equipment that is inside. For the purposes of this article, we’re going to ignore the ICT equipment element because that is a whole book in itself.

The data centre as a building clearly has three distinct phases, the design and construction, which can affect operations, the operational phases and the decommissioning phases. Studies have indicated that the design and construction phases can account for up to 30% of the total overall carbon emissions, the balance of 70% being from operations and decommissioning.

From a sustainability perspective, it is unfortunately like the wild west. In the absence of any globally defined definition as to what a sustainable data centre looks like, there are many claims that ‘this data centre is green’, ‘that data centre is sustainable’ and ‘that data centre is energy efficient’ - and yet none of them are using strictly defined globally recognised definitions. In short, a lot more work needs to be done.

Data centres use a great deal of electricity, even the most energy efficient and optimised facility will use vast amounts of energy during operation. A well-known search engine uses in the region of 2GW to power its facilities globally (that’s the entire annual output of Sizewell B Nuclear Power Station in Suffolk!)

From the Climate Change Agreement for Data Centres (2nd phase) we know that UK commercial data centres (colocation) data centres used 2.573TWh’s in 2017, which represented some 0.79% of the total energy consumed in the UK in 2017.

However, that data is ONLY for the commercial operators; enterprise data centres are specifically excluded, but they account for the vast majority of data centres in the UK. So, back in 2017, we undertook some research using business data, where we found that, actually, the total energy consumed by ICT was in the region of 38.54TWh - add the CCA figure and you get a grand total of 42.11TWh, which is around 12.13% of the total electricity generation in the UK.

Globally, the estimated figure is around 1% of total electricity generation being used for data centres, but this is likely to change significantly due to the hyperscale cloud growth and edge, even as high as 4% - although some commentators have suggested 20%.

EU Green Deal

These figures are seriously alarming governments, utility providers and the environmental NGOs globally, with the result that the sector is now under increasing focus. In the EU, this is being taken very seriously indeed, with the EC making a very clear statement to all data centre and telecommunications operators in February 2020: “Data Centres can and should be carbon neutral by 2030.”

We await further details on what improvements or even regulatory measures the EC will apply and even though the UK has left the EU, it is likely that such measures may be replicated here.

Standards and regulations

One of the main problems is the lack of a globally defined and agreed definition of what a green, sustainable and energy efficient data centre looks like, should be reporting etc. But is this really the case?

Before 2010, the data centre standards landscape was sparsely populated, in fact almost barren. The only ‘standard’ was the Uptime Institute Tier Topology and Certification Scheme and that really only covered uptime and resilience, not energy efficiency or sustainability. Since 2010 however, there has been a lot of work undertaken in this area.

We now have the ISO 30134 series of Data Centre Key Performance Indicators Standards; the EN 50600 series of Data Centre Design, Build and Operation Standards (including two technical reports); the EN 50600 TR-99-1 best practices for energy efficiency and EN 50600 TR99-2 best practices for Sustainability. The EN50600 series is also under consideration to become a full ISO - the ISO TS22237 series, which will be a true global Standard.

EU Code of Conduct for Data Centres (Energy Efficiency)

The EU Code of Conduct for Data Centres (Energy Efficiency) scheme, which was developed by the BCS Data Centre Specialist Group in conjunction with the Department for Agriculture and Rural Affairs (DeFRA) and the EU Joint Research Centre in 2009, continues to be an excellent reference point for energy efficiency and sustainability in the data centre (being the primary source for the two EN 50600 technical reports referenced above).

It contains over 160 best practices in the 12th edition, which was published earlier this year. The best practices provide strategic and cultural change management aspects, including training and it is recommended that all data centre owners and operators download and participate in the scheme. It is entirely voluntary and users can still download and adopt the best practices without becoming a participant, but the data required for participation is used by the EU-JRC for research purposes and is used as inputs to EC policy.

The data centre of the future

Between 2017 and 2020, the CATALYST project (a H2020 funded EU research project) aspired to turn data centres into flexible multi-energy hubs, providing energy flexibility services (supporting the grid), waste heat reuse (reusing the waste heat in data centres to offset energy costs elsewhere) and synchronising IT with renewable energy production (IT load shifting). This project was recently completed successfully and shows the direction of travel. It may be worthwhile to check out the CATALYST roadmap site which covers some of the options available.

To be considered carbon neutral, the data centre sector is going to have to collaborate with its near neighbours to provide the smart city of the future and provide energy flexibility, reuse its waste heat and become more energy smart.

The hyperscalers have already demonstrated that all of this is possible with facilities already connected to district heating schemes in the Nordics, Energy flexibility by schemes such as STOR which can be extended, search engines moving data that flexes with renewable energy production.

Innovative immersed liquid cooled servers are on the rise and this can be coupled with other circular economy concepts to provide a wide range of heating services to hotels, student accommodation and even apartment blocks and flats - the ‘digital heating’ concept. But, for these to work, organisations (both commercial facing and enterprises) need to become more innovative and collaborative.


The roadmap to cleaner, greener, European data centres is contained within the EU Code of Conduct for Data Centres (Energy Efficiency), the impending EU Green Deal where some legislation may be on the cards and the research projects that have been undertaken by various organisations in the FP6, FP7 and Horizon 2020 programmes.

The technologies to support cleaner, greener data centres are already largely mature but rare within the data centre industry - this will change.

It is possible to build clean, green, energy efficient and sustainable data centres and the direction of travel in Europe clearly indicates that if the industry doesn’t do it themselves, then regulations will be brought to bear.

About the author

John Booth is the Managing Director of Carbon3IT Ltd, an organisation that provides data centre support services such as ISO management standards, EU Code of Conduct for Data Centres (Energy Efficiency), sustainability and energy efficiency consultancy as well as training services. Carbon3IT Ltd also provides Green IT consultancy.

John is the Chair of the Data Centre Alliance - Energy Efficiency steering committee, the Vice Chair of the BCS Green IT specialist group and represents both organisations on the British Standards Institute TCT 7/3 Telecommunications, Installation requirements, Facilities & infrastructures committee. He is also the Technical Director of the National Data Centre Academy.