GRC Touts Server Immersion To Heat Offices

A radical way to cool your servers by submerging them in liquid could also potentially heat buildings

Green Revolution Cooling (GRC) has revealed a novel way to heat office spaces using its total immersion server system.

The Austin, Texas-based company showed off the system in March 2010, and this June said that it could reduce data centre cooling and energy consumption by up to 95 percent. Other companies, such as Hardcore Computer have also revealed liquid cooling systems for rack servers.

Di-electric Oil

Instead of vertical racks, the GRC CarnotJet System uses a horizontal system, so that blades are immersed in a bath of non-conductive (di-electric) oil, but each one can be accessed for replacement or repair.

The close contact between the mineral oil and the electronic components means that the fluid does not need to be much colder than the optimum operating temperature of the server to offer a much better cooling effect than air.

Green Revolution's four-rack installation

But now it seems this concept could also be used to heat buildings, after the company adapted its liquid immersion cooling system to recapture server heat. This server heat would be used to heat water for climate control systems.

“One of the biggest barriers to efficiency in the data centre industry today is the inability to recapture server heat without incurring extravagant infrastructure costs,” said the company in a blog posting. “Servers convert vast amounts of electricity to heat, most of which is wasted. Green Revolution Cooling is announcing the ability to recapture and reuse nearly 100 percent of server heat at a cost lower than most air cooling solutions.

It pointed to a July 2011 installation at the Royal Institute of Technology (KTH) in Stockholm that reliably produces water up to 50°C (122°F) – which GRC says is hot enough to pump to surrounding buildings for building heat. “Remarkably, this performance has been achieved with commodity servers and standard CPUs,” said the company.

Water Loop

As mentioned above, GRC’s CarnotJet system uses dielectric fluid that circulates freely through the servers, removing heat to a Pump Module where it is exchanged to a standard water loop.

“Typically, that loop is run to an evaporative cooling tower to reject the heat to the atmosphere, but it is also possible, as KTH is proving out, to reuse the heat from the water,” GRC said. “As testing continues at KTH, researchers will strive to produce 70°C water, which could be used to produce hot tap water, a useful commodity all year long.”

If this is achieved KTH will be able to recapture energy in addition to heat.

“Added to the energy savings produced by server fan removal, the system could outstrip even the most energy efficient CarnotJet system installations to date,” GRC said.

GRC has commenced testing with newer server hardware and it hopes to produce a full white paper by the end of the year.