Critics of the data center industry often describe it as something akin to a vortex, sucking power and natural resources into the void as part of the seemingly never-ending quest for denser racks and more powerful servers.

It is somewhat ironic, then, that startup H2OVortex is looking to harness the power of vertices to reduce water use in data centers and enable more efficient cooling systems.

The company has created an industrial vortex generator for cooling towers (IVG-CT) which it says can be applied to new and existing heating, ventilation, and air conditioning (HVAC) cooling systems in data centers and cut water and energy use, as well as eliminating the need for some chemicals.

H2OVortex has now fitted its technology in several data centers, and has also been given the thumbs up by industry body the Dutch Data Center Association, which recently co-authored a white paper recommending that its members investigate how the technology can be applied in their data halls.

H2OVortex: the face-off

The H2OVortex technology has its origins on the ice rink. The traditional method for building and maintaining the type of surface required for recreational skating or for a professional ice hockey rink is to pour hot water onto an already-frozen rink, a process known as flooding. Hot water contains fewer air bubbles than cold, freezes quickly, and helps create a smooth surface that is perfect for pursuing the puck.

Given that a single professional ice rink can, according to figures from the International Ice Hockey Association, use up to one million liters of water a year for resurfacing alone, the associated costs and environmental impact are significant. “It’s a ridiculous amount of energy,” says Alain Mestat, managing partner at H2OVortex.

Håkan Grönlund has experienced this issue firsthand. The H2OVortex co-founder is a former semi-professional ice hockey player in his native Sweden, and set about coming up with a more sustainable solution. The resulting Vortex-based technology, known as REALice, is a device that is able to remove air bubbles from cold water so that it can be poured onto the ice as part of the flooding process, eliminating the need for heating.

“We’ve reduced the operating costs of an ice rink arena by 40 percent, and have about 1,500 of those out in the market,” Mestat says. Happy customers include US NHL team the San Jose Sharks, which has installed the system on five rinks at its Sharks Ice headquarters, and expects to save 250,000 kWh of electricity, over 11,000 Therms of natural gas, and 230 metric tons of CO2 emissions each year as a result.

From the rink to the data hall

But what’s all this got to do with data centers? Mestat explains that his company has taken the core technology that sits at the heart of REALice and applied it to industrial cooling systems, such as those used for servers.

Explaining how the IVG-CT system works, Mestat says: “We specialize in biomimicry, so our system is really copying nature. It’s a nature-based solution, and we’ve looked at the intrinsic capabilities of a vortex to change water and industrialized that. By creating an artificial vortex, we are able to offer fantastic added value from a sustainability perspective.”

In fluid dynamics, a vortex is created when liquid revolves around a central axis. These are often seen in whirlpools, in the wake of boats, or in the bottom of the bath when you pull out the plug. The crucial characteristic of such vortices, from H2OVortex’s point of view, is that the action of spinning the water round and round changes its properties.

“Through the vortex, we can change the characteristics of the water,” Mestat explains. “We increase its density by five percent, and that makes it much more efficient as a cooling liquid. We also reduce the viscosity by 20 percent.”

This second point is important because, as the water becomes more liquid, it “requires less energy to travel from A to B,” says Mestat. And “if you spray it onto a surface, it will cover a much broader area,” he adds. “That’s very important in a cooling tower because if you are able to cover 85-90 percent of the surface you have a much more efficient system.”

The vortex is created by pushing pressurized water (Mestat says the system requires water pressure of three bar, the same as a regular feed from the mains) into the wide end of a cone-shaped, 3D-printed device which reminds DCD of a terracotta tagine. It doesn’t contain any tasty Moroccan stew, but is able to create vortices in addition to what Mestat describes as a “quasi-perfect vacuum” through a process known as cavitation. He says: “We create a vacuum at 0.97 bar and that crushes any living bacteriological or organic elements in the water - the system kills anything that is alive in the water on a continuous basis”.

Mestat claims this means the system can use any type of water without the need for any chemical intervention. While the use of non-drinkable, or “grey water” in data center cooling is already being explored by many operators - Amazon announced last year that 20 of its AWS data centers were using purified wastewater in their cooling systems - this usually has to be treated first to ensure it is ready to be circulated through a HVAC. Not so for H2OVortex, Mestat says. The system can use water of any quality, and at the end of the cooling process, discharge water can easily be collected and recirculated.

“We run all of our systems 100 percent chemical free,” Mestat explains. “The net benefit to a cooling tower at a data center is that we can reduce water consumption by up to 50 percent, though if it is using potable [drinkable] water that figure might be even higher. Our container will adapt to any type of water, so there’s no need to use potable water at all.”

The system is delivered in a shipping container which can be connected up to an existing HVAC system. The number of vortices required to cool a data center varies depending on the size of the facility, Mestat says.

“It’s a fully scalable system, so we ask our clients to fill out a data sheet and will run analysis on that to work out what is needed,” he continues. “The containers are stackable, so if it’s a huge HVAC we simply stack another one on top.” Clients can apparently expect a return on their investment in less than three years.

Going Dutch

H2OVortex is headquartered in Luxembourg, with its R&D work carried out by a team in Swedish city of Malmo, and its engineering done in Tilburg, Netherlands. Mestat, a former investment banker who spent years backing clean tech companies, initially became involved with the company as an investor, before joining the team full-time six years ago.

With an established presence in the Netherlands, it’s no surprise that it has found an enthusiastic user base, installing the system in a number of data centers, which Mestat says are operating in “mostly Edge” facilities.

In July, the company published a white paper with the Dutch Data Center Association (DDA) which demonstrates how the technology can be used by the industry. In an example cited in the white paper, an unnamed Dutch data center that installed the IVG-CT system was able to reduce its “potable water consumption by over 35 percent (from 95 m3/h to 62 m3/h).”

It continues: “Additionally, the data center achieved a CO2 emission reduction of over 83 percent. Even during an extended heatwave, operations could continue as usual, while the plant remained operational. This made water management much more controllable and resulted in significant savings.”

If the data center had also used alternative water sources, such as “surface water and wastewater,” the white paper says that potable water consumption “could have been reduced by 95 percent.”

The DDA said H2OVortex could help “mitigate water stress and contribute positively to local ecosystems.”

Stijn Grove, DDA managing director, says: "Engaging with stakeholders early, adapting systems used in other industries, and ensuring continuous monitoring and maintenance are essential to maintaining water-efficient operations. These combined efforts can help data centers not only avoid contributing to water stress but also become part of the solution.”

Backing from the industry will be critical if H2OVortex is to achieve wider adoption, Mestat says: “When you bring any new widget to market that is a disruptive and easy technology - pretty much what we’re saying is ‘put the water through here and all your problems are solved’ - it is going to take time for people to get that.”

The company is part of the accelerator program run by US water technology company Xylem, and Mestat expects it will pursue a joint venture with a larger organization to help market its technology. “We need a bigger brand name to achieve penetration,” he says. “In the Netherlands it’s easier for us because we have an engineering team on the ground, working and speaking Dutch. They’ve been doing this for ten years and can get referrals for new business.”

In the meantime, the company is pursuing a high-profile client and is in discussions with a hyperscaler looking to build a large data center in one of Europe’s warmest climates, which could deploy artificial vortices as part of its cooling solution.

Mestat says that warm environments, where water is already scarce, are likely to be the most fertile markets for H2OVortex. The US and the Middle East are obvious targets, but he says Southern Europe could prove lucrative, too.

“Our added value is going to be in areas where you already have water stress,” he says. “You have a bunch of companies at the moment setting up data centers around Barcelona in Spain, and Lisbon in Portugal. There’s already not a lot of water in these areas, and the idea is that we can complement developments in these areas.

“The data center industry is a powerhouse in terms of creating jobs and providing economic prosperity, but it has to be able to mitigate the issues it faces so that it can continue developing sustainably. We think we have a solution that can help.”