Water has been flowing in a closed circuit for 20 years now, cooling servers stacked on top of each other in OVHcloud datacenters. The first system of water coolinglaunched in 2003 by the Klaba family (owners of the company), was then only a test, first kept confidential for fear of scaring customers, before becoming a real trade secret, for fear of being to copy.
In two decades, the system has evolved, in particular with the arrival of smaller parts to more precisely cool the components that release the most heat on a server. After 2015, 3D printing allowed OVHcloud to continue to improve. Until this day. At the time of celebrating the anniversary of the system, but also at the time of replacing it.
OVHcloud water cooling
To celebrate this anniversary discreetly but surely, OVHcloud has invited our colleagues from 01net at the heart of its manufacturing in the Croix factory (where 300 servers are produced per day), a center of all the know-how of the French host that lemon squeezer had also been able to visit for a report. It is also here that OHVcloud produces the parts for its water cooling.
Miroslaw, the brother of Octave Klaba (President of OVHcloud), remembers the beginnings of the system, “at some point (Or) Octave had sent a press release announcing that we were doing watercooling, before backtracking and hiding behind the excuse of April Fools’ Day”, he explained. A fear of the risk of leakage that the team wants, even today, to dismiss by highlighting its O-rings, its welds and its sealing tests.
The last twenty years have not been all rosy, but there are not many leakage problems that said. The biggest dates back to June 29, 2017 in a Parisian datacenter. A particularly frustrating combination of circumstances for OVHcloud, responsible for several operating errors all occurring at the same time. For 24 hours, 50,000 sites were disconnected.
On the other side of the scale, an anthology of advantages. All are listed and detailed in the report of 01net, the interest of reduced electricity consumption, ease of installation of data centers and reduced environmental impact. “The great advantage of this device is that it allows us to densify the number of servers per square meter” added Grégory Lebourg, director of environmental programs at OVHcloud, to our colleagues.
Paradoxically, the use of water also distinguishes OVHcloud from… its water consumption. Compared to the competition, the Water Usage Effectiveness (a ratio measuring the efficiency of water use) puts the French company at just 0.26 liters of water per kWh of energy output, compared to an average of 1.8 liters “in conventional data centers” – notably at the GAFAMs.
Several surveys on their water consumption have scandalized many residents and associations fighting for the environment, such as in the Netherlands with Microsoft and Google. In August 2022, a survey by a local newspaper pointed to a consumption of 84 million liters per year for Microsoft, which only communicated on 10 to 20 million liters. Also in the Netherlands, a demonstration had made the Facebook group flinch, which also wanted to install a data center there.
© OVHcloud
OVHcloud will abandon water
Unlike its competitors, water is not an alternative to ventilation at OVHcloud. But after celebrating its twentieth birthday, the water cooling as we know it today will retire. Announced in October 2022, a new system called Hybrid Immersion Liquid Cooling arrive.
“Immersion cooling is the practice of immersing electronic devices in a thermally, not electrically conductive liquid”, presented the company a few months ago. In addition to water-cooled components, the new process will replace ambient air for a solution called Immersion Cooling – a dielectric liquid (which does not conduct electricity) – “a kind of oil” detailed Miroslaw Klaba to 01net.
The new bays, which will be able to hold 48 servers (no longer stacked, but arranged like books in a library), will offer a reduction in overall energy consumption of around 20% compared to the water cooling current. Sheltered from all dust, the new protocol would also reduce the risk of failure by around 60%. Its design, finally, would be “an instance de brevet”.
