The advantages of green cloud computing are many: lower costs, faster updates and simpler maintenance. And there’s also a nod to the socially conscious because it’s less taxing on the environment due to lower carbon emissions.
“Energy use is certainly an important consideration in the data center, and cloud solutions are more efficient than traditional systems,” said Eric Woods, research director at Pike Research Inc.
That’s important because recently, IT’s carbon footprint has been expanding. Between 2011 and 2020, worldwide
How now, green cloud?
A green cloud solution is more efficient than a traditional premises-based system in three ways. The first is more efficient provisioning. Historically, IT departments deployed more server, networking and storage infrastructure than needed. Businesses wanted to avoid potential capacity problems during peak usage periods. Consequently, they designed the systems to adhere to maximum usage periods; often, systems sat idle or underutilized.
Business dynamics also played a role. Corporations sometimes had difficulty understanding and predicting demand growth and peak loads, so they purchased enough capacity to be safe rather than sorry. And since corporate budget policies often encourage departments using all of their available funds in a given year and threaten a smaller allocation the following fiscal year, finances are also partly at fault for underutilization.
Multi-tenancy is another green cloud advantage. Shared infrastructures operate more efficiently than autonomous ones. Just as multiple tenants in an apartment building often use less power overall than the same number of people owning their own homes, multiple tenants of a cloud-provided infrastructure reduce their overall energy use and associated carbon emissions. In fact, disparate demand patterns from numerous companies flatten overall demand peaks and make usage patterns more predictable.
Using a cloud strategy also saves energy by improving server utilization – the measurement of the portion of a server’s capacity that an application actively uses. Large-scale cloud providers run their infrastructure at higher and more stable utilization levels than corresponding on-premise operations, so the same processing volume can be completed with far fewer servers. A typical on-premise application may operate at 5% to 10% average utilization rate, but the same application in the cloud may attain 40% to 70% utilization, thus dramatically increasing the number of users served per machine.
While it is true that servers running at higher utilization rates consume more power, the resulting increase is more than offset by the relative performance gains. Increasing the utilization rate from 5% to 20% will allow a server to process four times the previous load, while power consumed by the server may only increase by 10% or 20%.
Wallet-based motivation for a green cloud switch
So, what are the potential savings? Currently, there are no precise metrics, but market analysts have outlined what they see as potential reductions in carbon emissions – as well as energy costs.
A Verdantix survey projects that moving to a green cloud would enable corporations to cut carbon emissions by 85.7 million metric tons per year by 2020 and also reduce energy bills by $12.3 billion.
Pike Research forecasts that cloud data centers would consume 139.8 terawatt hours (TWh) of electricity in 2020, a reduction of 31% from 201.8 TWh used in 2010. This number also represents a significant decrease from the 226.4 TWh that would be consumed if firms made no changes to their systems. The reduction will drive total data center energy expenditures down from $23.3 billion in 2010 to $16.0 billion in 2020, as well as causing a 28% reduction in carbon emissions from 2010 levels.
However, the potential savings may be spread out unevenly. Ironically, large enterprises tend to benefit least because they may utilize advanced data center infrastructure designs – improved cooling systems and better power line conditioning – that already tend to reduce power loss and energy consumption.
An Accenture survey found companies with more than 10,000 users would reduce energy use and carbon emission by 30% to 60% by turning to a green cloud. Firms with 1,000 employees would see reductions of 60% to 90%, and small businesses with up to 100 users would see reductions of more than 90%.
Such metrics may tip a server evaluation to the cloud.
“Companies are taking environmental issues quite seriously and increasingly they are becoming a key part of the discussion about how to grow their data centers,” said Woods.
ABOUT THE AUTHOR: Paul Korzeniowski is a freelance writer who specializes in cloud computing issues. He is based in Sudbury, Mass., and can be reached at firstname.lastname@example.org
This was first published in June 2012