Our insatiable demand for computing power in an always-on, data-driven world is beginning to have serious consequences. In particular, the rapidly growing number of data centres around the world, especially hyperscale data warehouses, is absorbing valuable energy and water resources. It is, for example, estimated that the typical data centre uses between 11 and 18 million litres of water a day for system cooling; this is comparable to the water consumed by a small city of around 50,000 people1.
This situation is often exacerbated as data centres are constructed in regions where it is easier to generate wind or solar energy, or close to suitable infrastructure and major centres of population. In many cases, this means locating these facilities in areas where water resources are already under stress.
Not that long ago, the issue of sustainability was rarely a priority when constructing and operating data centres. This situation is now changing due to multiple drivers. These include increasing environmental, social and governance (ESG) targets, the commercial realities of the cost of energy and water, the result of consumer pressure and the recognition by data centre operators that sustainability is a critical element in brand reputation.
Consequently, major players such as Google and Microsoft are taking significant measures to reduce their energy and water consumption. Microsoft, for example, is committed to becoming ‘water positive by 2030, while the 74 data centre members of the Climate Neutral Data Centre Pact (CNDCP) has set of targets to reduce water consumption to 0.4l/kWh by 20402 for all data centres.
Water treatment for data centres
The good news is that new and existing technologies are available to help data centre operators make significant reductions in their water usage. These can either be built-in during the construction of a new data centre or retrofitted to existing facilities.
New cooling technologies include immersion cooling, where servers are immersed in a special dielectric liquid. These will, however, take time before they are widely used and they may not always be suitable for retrofitting to existing server systems. In the meantime, there is much that can be achieved through the use of proven water treatment, purification and recycling technologies.
For example, many data centres use large volumes of potable water. This can be reduced by both introducing rainwater harvesting and by recycling process water; typically, with appropriate treatment more than 70% of process water can be recycled. Alternatively, it may be possible to abstract water from a local borehole or, in cooler latitudes, to use seawater as a cooling medium. In each case, the raw water must be correctly treated and purified to eliminate potential problems in downstream cooling water systems caused by scaling, fouling, corrosion and the build-up of biofilms.
Similarly, improving the efficiency of existing evaporative cooling systems can help to reduce both energy and water consumption. For example, optimising cycles of concentration, to recover water that is otherwise wasted after blowdown water, and thus reducing the volume of make-up water required, can be achieved by carefully planned water treatment programmes.
At Purite, we’ve many years of experience designing and manufacturing high performance systems for use in data centres. We have a range of treatment and purification technologies, plus the engineering skills and resources to build packaged plant that is robust, low maintenance and complies with different regulations around the world. Most importantly, we can deliver the systems and support that help data centre operators reduce their energy costs and water consumption, while meeting ever tougher sustainability goals.
Find out more about our technologies and technical solutions for data centres.