Can the excess heat issue solve the data centre problem? 

It's getting hot in here 

Canva pic 1

Let’s take one ‘problem’ at a time. According to Uravu Labs’ own calculations, data centres ‘reject enormous quantities of low-grade heat (30–60°C) to the environment’. 

Where does this heat come from? Mostly, it comes from the energy used to power the servers and processors that increasingly run every aspect of our world, and the heat generated from the immense computational power involved. 

According to McKinsey, total global data centre power demand could reach 35-40 GW by decade's end, with AI workloads accounting for 25-30 per cent of new capacity additions. In 2025, data centres consumed 1.5 per cent of global electricity production; by 2030 this is expected to rise to 4 per cent.

All that electrical power becomes thermal energy; according to the Bloomberg report, a data centre using 50MW of electricity will generate the same heat as 54,000 homes. 

CNN reported that data centres are creating ‘heat islands’ in their local neighbourhoods, quoting researchers who found ‘surface temperatures increased by an average of 3.6 degrees Fahrenheit after a data centre started operations. In extreme cases, nearby temperatures increase by up to 16.4 degrees Fahrenheit.’ This increased warming was reported in the vicinity of data centre hubs in Mexico’s Bajio region and Aragon, Spain, but also extended as far as six miles from the sites.

Not as thirsty as they used to be

It is possible to read 10 papers or reports on how much water is used by an average data centre and come away with 10 different answers. Do opponents overestimate water consumption, or are data centre operators not sharing the full picture? There is the question of whether you include supply chain water use, such as in semiconductor manufacturing, and the almost exponential increase in demand for more processing power. 

As we have seen, the energy needed to power data centres is increasing, and by 2030 could represent four per cent of total global energy use, a 2.5-fold increase in the space of 3 years. Depending on the type of energy being used, this could have a big impact on local water use, increasing competition in areas that are often already water stressed. 

In an article on its website, Uravu Labs’ CEO Swapnil Shrivastav and the company’s Senior Scientist Dr Rishabh Srivastava point out that 60 per cent of data centre capacity through 2030 is located in regions classified as water-stressed by the World Resources Institute. “This creates regulatory risk, community opposition, and potential operational constraints,” they add, citing more than one billion gallons of water consumed globally every year by data centres – a figure that could rise by as much as 30 per cent a year. 

With changes in how modern data centres are cooled, the volume of water used within the facilities has decreased. Direct-to-chip and closed-loop cooling systems reduce water consumption dramatically compared to evaporative cooling towers, but there is a trade-off because they increase energy requirements. 

And as Shrivastav and Srivastava point out, every method of cooling data centres, whether water-intensive or not, treats generated heat as a waste product. 

Writing on his LinkedIn profile, Shrivastav, points out the dilemma:

“Air/dry cooling = no water, but the chillers burn extra electricity and stress the grid. And every kilowatt of that compressor power becomes more waste heat dumped locally,” he said. Before adding: “Evaporative cooling = far less electricity, but it drinks water and pushes humidity into the local air. So, water-stressed regions are backing away from it.”

He points out that you either ‘vent and stress the grid, or evaporate and stress the watershed. Two ways to pay.”

But what if that excess heat could be put to good use? 

Using excess heat to create and save water

In London, Aecom is developing a heat network that has the potential to channel that excess heat into offices and homes. This concept is established in other industries; for example, the Port of Rotterdam channels excess heat from its industrial users into commercial and residential properties. 

This addresses the problem of excess heat, but what about water? 

Uravu Labs is partnering with Imagine H2O Asia to turn the wasted heat and water conversation on its head, using Atmospheric Water Generation (AWG).

Specifically, the Uravu Labs approach uses a sorbent-based AWG approach to turn waste heat from data centre servers into distilled water for cooling, reducing freshwater use while keeping cooling energy demand low.

Imagine H2O Asia is facilitating the roll-out of this technology in data centre operations across the Asia-Pacific region. If the pilots are successful, it will prove that waste heat can be reused directly on site to produce water for cooling data centres.

Heat reuse: the way forward as data centres cluster and hyperscale

Uravu Labs uses a proprietary liquid-desiccant system that extracts water from ambient air. It does this using the following steps:
Absorption: Ambient air passes through a proprietary liquid desiccant solution that captures water vapour with extremely high efficiency across humidity ranges (20-90% RH)
Heat integration: Diluted desiccant is heated using 30-60°C waste heat from data centre cooling loops. This heat would normally be rejected via cooling towers, dry coolers or chillers and be expelled into the surrounding atmosphere, causing the problems mentioned earlier.
Desorption: Under a controlled partial vacuum, water is separated from the desiccant, condensed, and purified to drinking water standards.
Regeneration: Concentrated desiccant returns to the absorption cycle, creating a closed loop.
Cooling integration: The desorption process requires heat to drive evaporation and generate water vapour. Data centre waste heat provides the energy while simultaneously being cooled, reducing the demand on chillers.
Essentially, a problem (waste heat) has become a solution to both itself (heat released to the atmosphere) and another problem (water use).