How sustainable is cloud computing? The answer may surprise you — but it could also vary.
By some measures — and according to some sources — the cloud is very eco-friendly. From other perspectives, however, it's less so.
To provide a balanced look, let's examine five cloud computing sustainability facts, and consider what they say about the sustainability of the cloud computing industry.
1. Data Centers Account for 1-2% of Total Global Energy Use
One data point that suggests that the cloud is good for sustainability is the finding in a 2020 study that data centers consume 1% to 2% of all electricity globally.
What's even more interesting is that that figure does not appear to have changed since at least 2010, even though the number of data centers across the world, and the scale of the workloads running on them, has increased dramatically since that time. This suggests that data centers have become remarkably more efficient over time, and that moving workloads into larger, centralized data centers — like those offered by cloud providers — will reduce overall energy consumption.
From this perspective, the cloud would appear to be a pretty good thing from a sustainability perspective.
2. Cloud Customers Increasingly Want Low Emissions
Supporting that viewpoint is Gartner's prediction that, by 2025, the carbon emissions of cloud computing providers will be one of the top three criteria that businesses weigh when choosing a cloud platform. The prediction is based in part on a massive increase in efforts by businesses to reduce their carbon footprints since the start of the COVID-19 pandemic, Gartner says.
While this figure is a projection rather than actual fact, it's another reason to believe that the cloud computing industry is poised to continue becoming more sustainable over time.
3. Microsoft Purchased 1.3M Carbon Offsets in 2021
Here's a data point that could be interpreted as either a good or bad thing from a cloud computing sustainability perspective: In 2021, Microsoft (which owns, among other energy-hungry platforms, the Azure cloud) purchased 1.3 million carbon offsets.
Advocates of sustainable cloud computing may welcome this news as evidence of how committed cloud providers are to reducing their carbon footprints.
On the other hand, naysayers may point out that purchasing carbon offsets is hardly the same thing as actually reducing the emissions generated by cloud data centers. It's one thing to claim carbon neutrality by buying it through offsets; it's another to build data centers that are actually powered by emissions-free energy sources.
4. Amazon and Microsoft Claim They Will Rely Solely on Renewable Energy Sources by 2025
Those naysayers may be heartened by Amazon's promise that, by 2025, the company will be "powering its operations with 100% renewable energy." Microsoft makes a similar claim, stating that "by 2025, we will shift to 100% supply of renewable energy." (For its part, Google Cloud promises to operate on 24/7 carbon-free energy by 2030.)
These companies haven't offered many details about exactly how they will acquire renewable energy, but it appears they will rely on a mix of power infrastructure they build themselves (like AWS' solar farms) and renewable electricity sourced from third-party providers.
Critics might still contend that Amazon and Microsoft are only able to pursue this goal because they have the deep pockets necessary to invest in renewable energy plants and to buy renewable energy at whichever price the market demands. In that sense, these renewable cloud computing energy plans — which hinge on big spending — are not that different from purchasing carbon offsets, which is also a luxury available to well-heeled businesses.
But that criticism seems a little unfair. The fact that cloud providers such as Amazon and Microsoft want to source renewable energy for their data centers, then make those data centers available to customers, would seem to be a good thing overall. It places clean-energy IT infrastructure within the reach of businesses that otherwise would not be able to afford to source clean energy, if they were running workloads in their own data centers.
5. Cloud-Native Technology May Save Energy
A final consideration in favor of viewing clouds as sustainable is the fact that, on the whole, cloud-native technologies such as containers and Kubernetes can achieve lower overall energy consumption than traditional technologies like virtual machines.
Of course, not all workloads running in the public cloud are cloud-native. And you can run cloud-native workloads outside of the cloud. (The term "cloud-native" is misleading in that sense.) But the cloud is the more obvious place to host cloud-native workloads, and in that sense, the widespread adoption of energy-efficient cloud-native technology is poised to make the cloud even more sustainable.
Although the cloud doesn't have a perfect track record when it comes to sustainability, most data suggests that, on the whole, cloud-based workloads are more eco-friendly than those running in conventional data centers. And that trend is likely to become more pronounced going forward, as cloud providers invest further in renewable energy sources and as more workloads shift to environmentally friendly cloud-native formats.
About the authorChristopher Tozzi is a technology analyst with subject matter expertise in cloud computing, application development, open source software, virtualization, containers and more. He also lectures at a major university in the Albany, New York, area. His book, “For Fun and Profit: A History of the Free and Open Source Software Revolution,” was published by MIT Press.