ETH Zurich: new Aquasar water-cooled supercomputer goes into operation

A water-cooled supercomputer using 40 per cent less energy than its air-cooled counterparts went into operation at ETH Zurich last week. The heat from the Aquasar computer goes directly to heat the building where it is housed, setting new standards in energy efficiency and reducing CO2 emissions by up to 85 per cent.

Aquasar was developed in a collaboration between ETH and IBM under a project that started a year ago to develop energy-saving and environmentally friendly high-performance computers and data centres.

“With Aquasar we are making an important contribution to the development of sustainable high performance computers and computer systems. In future it will be important how efficient a computer is, per watt and per gram of CO2,” said Dimos Poulikakos, Project Manager and Head of the Laboratory of Thermodynamics in new technologies, at ETH Zurich.

Energy consumption has become a central focus of computer development. According to market analysts IDC, in 2009 the computers worldwide consumed an estimated 330 terawatt hours of energy. Existing air cooling typically used in data centres accounts for up to 50 per cent of the total electricity demand. Liquid cooling, however, is far more effective: water has, approximately, a 4,000 times higher heat capacity than air and can therefore transport heat very efficiently. This allows new cooling concepts - such as the cooling of hot water - that are sustainable both economically and environmentally.

The construction of the Aquasar computer is part of a three-year collaborative research programme, “Direct use of waste heat from liquid-cooled supercomputers: the path to energy saving, [low] emission, high performance computers and data centres.” The project also involves ETH Lausanne and is supported by the Swiss Centre of Competence of support for energy and mobility (CCEM).

Bruno Michel, manager of Advanced Thermal Packaging at IBM Research in Zurich, said, “With the commissioning of Aquasar we have reached an important milestone on the road and CO2-neutral data centres. This is an important signal for the industry.” Now the research focus moves onto detailed studies on the performance and characteristics of the cooling system in order to optimise it further. To support this work the machine is specially equipped with an extensive system of sensors.