How can we prioritise sustainable water use in data centres? David Watkins, Solutions Director at VIRTUS Data Centres, shares his thoughts.

At the heart of our digital existence, data centres quietly hold the key to all that we do. From streaming our favourite shows to managing our finances and accessing a world of information, data centres are the silent architects of convenience and connectivity. 

However, their usage and growth need to be managed both economically and sustainably. The rapid proliferation of data centres has understandably led to critical questions being asked about their environmental impact, particularly concerning water usage in cooling technologies. 

The big water issue

As data centres expand to meet an ever-increasing demand which is being fuelled even further by AI, some facilities require significant amounts of water for cooling and other operational processes in order to keep systems running. In some cases, this reliance on water resources can place stress on local water supplies, causing concerns about water scarcity in regions already grappling with this challenge. It’s been the subject of some headlines and understandably people within and outside the industry are concerned.

According to research carried out by Savills, it is thought that a data centre may use up to 26 million litres of water each year, on average, per megawatt of data centre power. Although this appears to be a worrying statistic, it should be acknowledged that unnecessary water leakage caused by water companies is also a major reason for concern. According to OFWAT, in 2020-21, England and Wales leaked 51 litres of water per person per day, and in Scotland and Northern Ireland this figure was above 80 litres of water.

What should also be understood is that many large data centres use ‘closed loop’ chilled water systems – meaning that water is charged into the system during construction and then continually circulated within a facility, rather than needing new water consistently pumped into the building. A large-scale data centre will be filled with around 360,000 litres of water initially, or the equivalent of a 25 metre local swimming pool. This water will remain in the system for the lifespan of the data centre, typically a minimum of 15 years. 

Committed to innovation

It should also be recognised that the data centre industry has long been committed to ensuring sustainability and efficiency, with providers working hard to use resources including power and water responsibly. In response to these challenges, data centre operators are embracing innovation as a cornerstone of their sustainability efforts. Indeed, companies in the sector are continually looking to innovative sustainability strategies that include ‘green’ renewable sources of power, rainwater harvesting, zero water cooling systems, recycling, waste management and much more. 

A good example of this in practice is the strategic re-evaluation of cooling equipment. By altering the point in the cooling cycle at which water is introduced, operators can make substantial reductions in water consumption. Implementing this approach, along with other efficiency initiatives can save up to 55% of water consumption, and reduce the use of associated consumables such as water filters and associated maintenance. These kinds of innovative approaches help to ensure that water usage is minimised precisely when and where it matters most – during periods of the highest outside temperatures and in areas subject to water shortage.

In a significant shift towards sustainability, an increasing number of data centre operators are opting to only use renewable energy sources to power their facilities. This transition not only serves to substantially reduce their carbon footprint, mitigating the environmental impact of their operations, but it also reaffirms their commitment to sustainable practices.

Leading by example

By managing the point in the cooling cycle at which water is introduced, VIRTUS has achieved significant reductions in water usage; for example, at our LONDON2 data centre in Hayes, London.

In the UK, where ambient conditions provide the ideal backdrop, VIRTUS harnessed adiabatic cooling technology to cool the data halls efficiently. Leveraging the day/night cycle, free cooling was implemented to maintain the desired temperature within the facility. LONDON2 is also located above a natural aquifer, enabling the use of water that is not drawn from the public supply.

VIRTUS also powers facilities with 100% renewable energy sources combined with Power Purchase Agreements (PPAs). These agreements allow operators to directly purchase energy from a renewable energy provider over a set period of time. Companies that do this help the renewable energy industry to finance new renewable projects, increasing the availability of renewable energy on the market, and supports the growth of sustainable energy generation. 

Collaborative responsibility

Like so many major challenges, it’s important to remember that achieving sustainable data centres is a goal that cannot be reached in isolation. It necessitates industry-wide collaboration and knowledge-sharing to make real change possible. Data centre operators are already coming together to share best practices, techniques, and insights, with a particular focus on water-saving strategies. This collaborative approach augments the impact of sustainability initiatives and accelerates progress toward shared environmental objectives.

The collective responsibility of the data centre industry to reduce its environmental impact is an inspiring model that other sectors should learn from. As data centre operators unite in their commitment to sustainability, they set a powerful precedent for industries worldwide. They demonstrate that sustainability is not just a buzzword but a tangible goal that can be achieved through creativity, innovation, and concerted effort.