A computer as big as a house

The world’s fastest computers are located in China, the USA and Japan. But now the “Green Cube” supercomputer is under construction in Darmstadt, Germany.

It’s as big as a house and is expected to be extremely energy-efficient. At least according to its architect, physicist Volker Lindenstruth. The professor at Frankfurt’s Goethe University reports on his ambitious project for Industry Journal.

In 2018, the “Green Cube” will begin analyzing vast amounts of data – output from the Facility for Antiproton and Ion Research in Europe (FAIR), one of the world’s largest facilities for basic research in physics.

High-powered computers like this convert so much electricity into heat that they need to be cooled at great expense. “Current data centers have a power usage effectiveness (PUE) of 1.6 to 1.7,” Lindenstruth says. “For the Green Cube, we’re aiming for a PUE of not more than 1.1.”

How can that be done? “We have a free hand to choose components, and can pay attention to how much power each one consumes,” says the designer. As examples, he mentions the graphics cards that speed up the computer. Since their capacity is seldom fully used anyway, he and his team decided for graphics cards with the highest energy efficiency.

A role model for cooling

Lindenstruth also plans to save energy in cooling the supercomputer. His Green Cube is water-cooled. The cooling water, which ends up heated as high as 30 degrees Celsius, can be used to heat office buildings and the cafeteria at the site of the GSI Helmholtz Center for Heavy Ion Research.

Up to 90 percent less electricity

Lindenstruth and his team have already shown in Frankfurt that refrigeration really can take up to 90 percent less electricity. Frankfurt is the location of the Loewe-CSC supercomputer, with a capacity of about 300 teraflops, or 300 trillion calculation operations per second. It’s been running very reliably since the end of 2010. “On the Loewe-CSC, with a power consumption of 400 kilowatts, we’ve already been able to lower the cooling overhead to seven percent,” says the professor of high-powered computer architecture.