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REPORT FINDS WAY TO SLASH COOLING ENERGY USE AT DATA CENTRES BY UP TO 56 %
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A new study ‘ The global energy impact of raising the space temperature for high-temperature data centres ’ by Zhang Y . et al in Cell Reports Physical Science has found massive energy savings in redesigning servers to operate at hotter temperatures instead of looking for new methods – and energy – to cool data centres .
Data centres are vitally important in keeping modern society running but these are energy hogs , with their energy use per square metre up to 100 times that of typical office buildings , finds the report . Cooling accounts for over one-third of data centre energy consumption , yet operating those data centres at a higher temperature could save up to 56 % of cooling energy , according to the new study . The study suggests redesigning servers so that less active cooling is needed .
Early servers overheated easily , and data centres were kept so cold that technicians had to wear warm clothing . That legacy in turn led to a wrongful perception that ‘ colder is better ’ when it comes to data centre operation . Since then , advances in technology have produced more robust servers that can run at temperatures over 30 ° C , yet the report found that most data centres still operate at 20 – 25 ° C .
Data centres are kept cooled by running the air – which has become heated by the server operation – over coils of water to lower its temperature . The water in the coils in turn is kept cold either by using chillers or in colder climates by taking advantage of colder outside air , known as free-cooling and which uses much less energy compared to chillers .
In the study , the researchers posed the question of what it would take to push the use of free-cooling to the absolute maximum . They used weather data from 57 cities to model the operation and energy use of data centre cooling systems across 19 climate zones worldwide .
With an operating temperature of 41 ° C , data centres all over the world could rely almost entirely on free-cooling year-round , the researchers report . They call this the ‘ global free-cooling temperature ’.
Data centres operated at 41 ° C could use 13 – 56 % less cooling energy compared to data centres kept at 22 ° C , depending on the climate zone . Those in cold climates already make substantial use of free-cooling , with consequently less opportunity for energy savings than a warmer climate such as South Africa .
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The volume of equipment in large data centre server rooms creates considerable heat and requires extensive cooling facilities , leading to high levels of energy demand .
In order for data centres to operate at 41 ° C , engineers will have to develop servers that are reliable , don ’ t lose computational efficiency , and don ’ t show increased energy consumption due to activation of built-in cooling fans at that temperature .
Some of the most advanced servers available today can already operate at maximum temperatures of 40 ° C or 45 ° C . However , these machines are expensive and not in wide use – but indicate where technology is headed .
The findings provide server engineers and data centre designers a concrete goal to work towards in developing the next generations of servers and data centres , the researchers say . RACA
SOURCE Zhang Y . et al . ‘ The global energy impact of raising the space temperature for high-temperature data centres ’. Cell Reports Physical Science 2023 .
REFERENCE AND CREATIVE COMMONS LICENCE
1 . The global energy impact of raising the space temperature for hightemperature data centers - ScienceDirect
2 . CC BY-NC-ND 4.0 Deed | Attribution-NonCommercial-NoDerivs 4.0 International | Creative Commons
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