Data centres go energy efficient
New research suggests there’s no longer a close link between more cloud computing and increased energy use
This has been the decade of the data centre, which can be measured in a 10-fold increase in traffic and a 25-fold jump in worldwide storage. The surge was thought to come with a steep cost for the climate, since all those racks of servers run hot enough to require special cooling systems and vast amounts of energy.
But data centres are rapidly becoming more energy efficient, and new research suggests there’s no longer a close link between more cloud computing and more energy use. A report published on 28 February in Science credits the progress to better management, more efficient hardware and the rise of “hyperscale" data centres created by tech giants.
Back in 2010, according to the report, data centres globally used about 194 terawatt hours of electricity—about as much power as Iran used that year. By 2018, that figure had increased to 205 TWh. That’s a 6% rise in power use, in a period that saw data-centre computing grow by 550%.
The data-centre industry’s 20% annual improvement in energy intensity dwarfs all other major parts of the economy. The power used today by data centres, 1% of the global total, is roughly the same as it was in 2010.
This was an unexpected result. Analysts have extrapolated the incredible rise in cloud computing on to data-centre electricity consumption “leading to unreliable predictions of current and future global data centre energy use," according to the report in Science. Instead of collecting and analysing power-use data, some researchers had been taking the growth factor seen in data-centre internet traffic and assuming energy use was growing just as quickly.
This new research is the first major attempt to compile a bottom-up view of data-centre energy use in a decade. Researchers based their work on reports published by Cisco Systems, Inc., Lawrence Berkeley National Laboratory and the International Energy Agency, among other sources.
“We don’t have nationally reported statistics for data centres," says Eric Masanet, lead author and a mechanical engineering professor at Northwestern University. That created a lot of work for him and his colleagues. “We don’t see these estimates come out very often."
In a blog post on 28 February, Google celebrated the findings and touted the company’s own efforts at buying renewable power and cutting energy use. Urs Hölzle, senior vice-president for technical infrastructure, wrote that Google can now harness about seven times as much computing power from the same amount of energy as it could five years ago (Google and its parent company, Alphabet Inc., were not involved in the research by Masanet’s team or its funding).
Can the trend continue? The rise of hyperscale data centres and potential for better efficiency in storage means that computing and power use may continue to diverge, at least through the next doubling of data-centre workloads, which is estimated to take three-four years.
Masanet and his co-authors recommend policy changes to support continued efficiency gains. Government efforts such as the Energy Star program in the US can include servers and networking equipment. Renewable energy can play an even bigger role in data centres through tax credits and procurement standards. Finally, there can be better data about data centres.
“Data centres are becoming way too important to not rally more research behind them," Masanet said.
FIRST PUBLISHED06.03.2020 | 01:13 PM IST