Researchers in the UK believe the energy needed to cool global data centers run by giants like Facebook and Google could be cut by more than 90 percent by replacing air cooling with non-conductive liquids.
The energy needed to run the Internet and other cloud computing storage systems is estimated to represent around two percent of the world’s total energy consumption.
More than half of that is spent on running fans to cool down electronics in servers, which run hot, just like in personal computers.
Now a small British startup-company, Iceotope, is proposing their liquid-based cooling technology could dramatically cut the energy needed for cooling, while re-using the heat taken out of the computers.
“If we just look at the data centers – those factories of cats doing strange things on YouTube – the latest research suggests that this year alone those will consume 43 gigawatts of energy. It’s the equivalent to around 90 medium-sized nuclear power stations,” Iceotope’s Richard Barrington told DW.
“More than half of that energy globally is used just to cool the computers,” says Barrington. “So half of it is productive, the other half in one sense is unproductive. And then all the heat that is actually generated at the moment is just thrown away.”
Barrington believes using liquid rather than air cooling could be more than 1,000 times more energy efficient, saving data storage companies money and reducing their carbon footprint.
It would represent a reduction in energy used for cooling of between 80 and 97 percent.
Anyone who has used a laptop will know how hot even a small computer can get.
Although using fans to cool electronics down is not particularly efficient, it is the solution used in most of the world’s computers.
Iceotope teamed up with researchers at the University of Leeds in the North of England to investigate how to immerse the heat-generating electronics in a liquid, which would not damage them.
“We use a liquid which has a high dielectric strength – it doesn’t conduct electricity,” explained Dr Jon Summers at the school of mechanical engineering at the University of Leeds.
To demonstrate, he filled a beaker with the liquid and sank a mobile telephone into it.
“It’s a fully operational mobile phone. And one of the things we can do to test that it is still alive is to ring it while it’s inside the liquid,” explained Dr Summers. The mobile telephone did indeed still work, and appeared entirely undamaged when taken back out of the liquid.
Closed, recyclable system
Large data centers can house hundreds, sometimes thousands of computer server racks.
A typical server rack is the size of a wardrobe and houses around 40 individual servers – large computers that are far more powerful than your household variety.
In the Iceotope system each server is completely enclosed and the liquid is contained within – just like a laptop computer filled with liquid rather than air.
The servers’ liquid cooling system links up when they are plugged in, and it only takes an 80 watt pump to circulate the liquid around all of the servers in one rack.
“The system is a totally encapsulated solution, so the liquid is always there – it doesn’t evaporate,” says Summers.
Other liquid cooling systems submerge servers in big, open tanks of liquid, which are prone to evaporation and are also incompatible with existing data centers.
Servers heating buildings
But slashing electricity usage for cooling is only one half of the solution the Leeds researchers and Iceotope are looking at.
The heat generated by the machines still has to go somewhere.
While fans just blow hot air out of a building, this new system uses heat exchangers which pass the heat picked up by the non-conductive cooling liquid over to a separate loop, which uses ordinary water.
“It is low grade heat, but we find ways to use it,” says Dr Nikil Kapur, who is responsible for the project’s heat recycling research. “It would be ideal for space heating or underfloor heating for residential apartments. Other uses for low grade heat includes things like greenhouses, tomato growing is one that we often see.”
The Iceotope server installed at the University of Leeds heats up two conventional radiators.
Data giants like Google and Facebook are already looking at ways of slashing the enormous costs of cooling their giant data centers. Google recently unveiled plans for new data centers in the Arctic north, making use of the cooler air there.
Richard Barrington from Iceotope welcomes the development, but believes Google’s solution too is unsustainable in the long run.
“We can’t put all the data centers in the far north,” Barrington says.
“There isn’t sufficient capacity of people, power and floor space to do that. And we still need data centers in the Middle East, in high temperature environments. Emerging economies where they want to develop their own infrastructure, they’re not going to want to ship it out to Norway or Iceland.”
So far Iceotope has only installed two fully working liquid cooled server systems. One at the University of Leeds and one at a university in Poland. It is not exactly making a dent in the world’s enormous computer energy consumption – yet.
But if this technology can be proven to work on a large scale, and giants like Google and Facebook come knocking, the future of global computing could be looking far cheaper and greener than it is today.