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Digitalisation — and the associated data centres filled with stacks of servers transmitting, processing and storing information — is key to the energy transition. But data centres must also decarbonise: accelerate their push into renewable energy and continue efficiency efforts that have capped energy consumption growth in recent years
RESPONSIBILITY
Regulators and companies must work together if data centres are to maximise their energy efficiency potential REQUIREMENTS
More information about data centres and their energy use is needed to find the best energy saving solutions, as is better targeted research and development KEY QUOTE
“It is the ultimate irony that the industry that was built on data doesn’t provide data” Climate-neutral, highly energy efficient and sustainable data centres are what the European Commission, the EU executive body, wants to see by 2030. In February 2020, the Commission set out its strategy to meet the “twin challenge of a green and digital transformation”. Describing digital technologies as a “critical enabler” for Europe’s plans for climate neutrality by 2050, the strategy says they can pave the way for less waste of energy, a higher uptake of renewables and smart energy systems. But more data also means more energy demand. Information and communication technology (ICT) already accounts for more than 2% of global greenhouse emissions, or as much as all air traffic, says the Commission, warning the sector’s carbon footprint could balloon if action is not taken. The burden for taking action does not lie with companies alone. The European Commission is looking to support continued research & development (R&D) investments in computer microchips that consume less energy and to help less efficient, cash-strapped data centres to carry out upgrades. Energy efficiency efforts are nothing new for energy guzzling data centres. Despite a 550% increase in global computing from 2010 to 2018, the sector’s electricity demand rose by just 6%, to 205 terrawatt hours, according to research by Koomey Analytics published in the journal Science in February 2020. That is about 1% of all electricity use, unchanged from 2010. The energy intensity of global data centres decreased by 20% annually in the past ten years, Koomey Analytics reports. “The shift to cloud computing is probably the biggest factor [behind efficiency gains],” says the firm’s Jonathan Koomey, one of the researchers involved in the study. “Cloud data centres tend to have higher utilisation of equipment, but also lower overheads,” he says. “Together the two are important in lowering emissions and keeping energy use from growing significantly.” MORE POTENTIAL Overhead energy costs for large cloud data providers, such as those for cooling backup electricity and lighting, have decreased dramatically, as indicated by falling figures for power usage effectiveness (PUE, or the total amount of energy used by a data centre divided by the energy used by its IT equipment alone). While a PUE of 1.0 would mean there are no overhead costs and energy is used exclusively to power IT equipment, the best performers now report PUEs of around 1.1. The ratio varies significantly, however, and the typical corporate data centre may have a PUE approaching 2.0, with overhead energy costs that nearly match those for its IT energy needs, Koomey says. Cooling, in particular, used to be “massively inefficient”, says Arman Shehabi, a research scientist at Lawrence Berkeley National Laboratory, who also worked on the study. That problem has been largely solved in newer data centres, with better building design and equipment layout that have optimised air flows and the use of on-site resources, such as cool outside air or seawater for cooling. While much has already been done on the efficiency front, by tapping into the remaining potential currently available, the current volume of computations by data centres could double without any major increase in energy consumption, says Shehabi. “A lot of this requires policy,” he says, to push companies and IT managers to operate data centres differently through tools that strengthen and promote efficiency standards. The Energy Star efficiency standard — a joint initiative between the US Department of Energy and Environmental Protection Agency (EPA) — for servers, storage and network devices was introduced after data centre electricity demand doubled between 2000 and 2005. It has been a major driver of innovation, Koomey points out. Given the possibility computing demand could double in the next three to four years, there is no room for data centre operators or policymakers to be complacent. “Diligent efforts will be required to manage possibly sharp energy demand growth once the existing efficiency resource is fully tapped,” researchers caution in the Science article. Going forward, it is essential to have support for research and development of the next generation of ICT equipment that will boost efficiency gains, says Shehabi. Better data, to improve monitoring of the energy use of data centres and the drivers behind this use, is also important, he adds. Such information can be used to craft effective policies to cut the sector’s carbon footprint. “It is the ultimate irony that the industry that was built on data doesn’t provide data,” states Shehabi. This lack of information is often blamed on competition concerns, but Shehabi suggests it could be collected by a government body on an aggregate basis to allay such worries. NON-STOP RENEWABLES SUPPLY As data centres aim for carbon neutrality, they are buying more renewable energy and a number of US tech heavyweights have set goals for 100% renewables supply, including Facebook and Microsoft. Google, the world’s largest corporate buyer of renewable energy, has covered 100% of its annual energy needs with renewable energy since 2017, primarily through power purchase agreements (PPAs) with dedicated renewables suppliers. In practical terms, this means it buys wind and solar energy in regions or hours when it is abundant to compensate for the use of carbon-based energy at other times or in other places when green energy is not available. The company wants to go further and is now working towards a longer term objective of sourcing exclusively carbon-free energy around the clock, a task that is accomplished more easily in certain locations. The facility that comes closest is Google’s data centre in Hamina, Finland, which benefits from a number of PPAs with wind power producers and the country’s largely carbon-free grid, dominated by hydro and nuclear power. COAL-POWERED CHINA In China, the world’s second largest market for hyper-scale data centres and one which is growing rapidly, 73% of the electricity consumed in 2018 was procured from the grid and generated from coal, with just 23% from renewables, despite China’s vast quantities of wind and solar capacity, according to Greenpeace East Asia and the North China Electric Power University. “The climate clock is ticking and they need to step up their commitment,” says Greenpeace climate and energy campaigner Ye Ruiqi. Ye says there are signs of progress in China. E-commerce mammoth Alibaba buys wind power from local wind farms for its data centre in Zhangbei in Hebei province; tech company Baidu and data centre operators GDS and Chindata also each operate a data centre powered largely by wind and solar energy. Chindata in December 2019 became the first Chinese tech group to set a 100% renewable energy target. “The government needs to take steps to make the market for sourcing renewable energy more accessible,” says Ye, “But it’s a two-way street and companies also need to show they are committed.”
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Heather O’Brian