For the past ten years, data centre operators have faced scrutiny for the huge amounts of electricity used to store digital information. In the face of climate change, the amount of water they require to cool their facilities is becoming the next big challenge.

For developers, operators or investors, it is important to consider the availability and security of water supply before taking on a specific data centre. In Europe, it’s no surprise that the Nordic countries are the least at risk of water shortages (according to the latest data from Aquastat), as they benefit from large domestic water resources. Ireland, France and Italy have relatively good renewable water resources per capita and a low dependent ratio - below 10 per cent. Despite this, all of them need to prepare for the future, as demand is expected to grow in line with the increasing amount of data storage requirements.

According to Graphical Research, the total European data centre cooling market (including air and liquid cooling), stood at $3.5 billion in 2020 and is anticipated to rise by 15 per cent per year between 2021 and 2027.

On average, a single data centre uses 26 million litres of water each year, per megawatt of data centre power. Based on this figure, and assuming that 20 per cent of all existing European data centres use liquid cooling systems, the amount of water used by data centres on the continent would reach 43.2 billion litres annually. As a result, water will become increasingly important when deciding where to build a new data centre.

In 2022, the Climate Neutral Data Centre Pact (CNDCP), a self-regulatory initiative signed by 74 data centre operators and 23 associations, presented its proposed metrics for water conservation to the European Commission. The CNDCP’s target is to cut water usage to a maximum of 400ml per kWh (400 litres per MWh) of computer power by 2040. This voluntary goal is highly ambitious, but demonstrates the commitment of the European data centre industry to reducing its impact on the environment.

So how can data centres become less thirsty? Best practices for reducing water usage include alternative cooling methods such as air cooling or evaporative cooling, which use far less water than traditional water-based cooling systems. However, comparatively, they can use a lot more energy.

Data centres can also improve efficiency by implementing closed-loop cooling systems where the same water is recirculated within the cooling system and does not need to be replenished from an external source. There are a number of direct design efficiencies that can be made, such as virtualising servers and regularly maintaining cooling systems.

In March 2023, Google announced that it is working on new cooling technologies that could dramatically reduce the use of water in their data centre operations. While details of the technology are still under wraps, the company is targeting to cut its water usage by 50 per cent. This will not be enough to meet the CNDCP target, but it would be a significant step forward for the sector.

Further information

Contact Lydia Brissy or Scott Newcombe

Spotlight: European Data Centres