IT administrators grapple with two simple truths: The flow of data will never dry up, and energy costs will never drop.
But SSD storage could help as part of an overall strategy for keeping energy costs of data centers in check as they handle ever-growing amounts of data. Especially since the simple option -- turning off equipment you don't need, like a light in an empty room -- really doesn't apply to the 24/7 uptime expected of business IT.
"Near term, expanding the focus from energy avoidance (e.g. powering down or not using energy) to making more effective use of available resources … SSDs [solid-state drives] are a great way of doing more work in a given energy and physical footprint and, when evaluated on a cost-per-work or productivity basis, are an economic bargain," according to Greg Schulz, author of The Green and Virtual Data Center. "However, keep in mind that they also need to be combined with storage space capacity optimization and applicable technologies."
24/7 data centers -- at a cost
According to IDC Corp., the amount of data created and replicated isn't shrinking: More than 1.8 trillion gigabytes were made in 2011, while Cisco Systems Inc. predicted data centers across the planet would handle a total of 4.8 zettabytes by the end of 2015. Cisco also reported that, since 2008, most Internet traffic has originated or terminated in a data center.
There's a cost to handling all that data. Consulting and research firm McKinsey & Company found the cost of running a data center could account for half of the company's total carbon footprint, plus the cost of launching a data center for a large-scale enterprise grew from $150 million to $500 million between 2003 to 2008. Running those data centers consumed the same amount of energy needed to power 26,000 homes, the firm reported.
A separate Greenpeace study estimated data centers consumed 1.5% to 2% of the world's electricity, and that use grows at a rate of about 12% each year. The environmental advocacy group also pegged the total energy use of the world's data centers at 330 billion kilowatt hours in 2007, which they said was close to the total electricity demand in the U.K.
All that electrical use comes with a large carbon footprint. McKinsey noted that the world's data centers generated a total of about 80 megatons of carbon dioxide each year in 2008 and predicted that amount to reach 340 megatons by 2020. By comparison, Argentina's total carbon footprint was 142 megatons, according to the same study. Greenpeace reported many large technology companies -- including Google, Apple, IBM, HP and Facebook -- still rely on coal as a source of power.
Dennis Martin, founder and president of Demartek, has talked about the potential energy savings of solid-state storage devices, when compared to their enterprise-class spinning disk equivalents.
In a 2012 seminar, Martin noted that a 3.5-inch, 15k drive consumes anywhere from 13 to 19 watts of electricity during use, and eight to 14 watts when they're left idle. He noted that every watt used by computing equipment requires another watt of electricity to cool it.
By comparison, a SSD could use one to eight watts during use, and as little as less than half of one watt when left idle, according to Martin.
"If you're thinking about being green and that sort of thing, SSDs are a great way to do it," Martin said. "And, if you have power companies come to you and say, 'We can't give you any more power', you're going to have to do something. SSDs are a great way to make that happen."
But concerns about environmental impacts and efficiency around data centers in recent years has given rise to "greenwashing" -- the practice of positioning a product or practice as more eco-friendly than it actually is.
"Some vendors have tried to play the 'green' angle with SSD, HDD [hard disk drive] as well as with hybrid HDD. However the greenwashing stigma from a few years ago tends to cause these messages or themes to fall on deaf ears," Schulz said. "Vendors can do a … better job communicating the value of not just storage efficiency [and expand] the discussion to storage effectiveness and productivity such as more work done per watt of energy while maintaining and enhancing service, availability and response time. "
SSD total cost of ownership
According to Schulz, comparing a SSD vs. a HDD to make an energy ROI can be tricky, but not impossible.
"For example, if you have 16 x 2.5-inch 15K HDDs each drawing about 8 watts to get 3,520 IOPS, and replace those with a pair of 2.5-inch SSDs (mirrored) drawing 5 watts each, that’s an energy savings of at least about 118 watts," he wrote in an email to SearchSolidStateStorage.com. "However, on an annual basis, that is about 1,033 kWh, which at say 20 cents a kWh, works out to about $207 USD savings a year."
He then went on to compare that savings to the cost of the drives themselves. "Let’s say for fun that the two SSDs cost $1,000 each for a total of $2,000 USD and that they can be installed into an existing storage system with no other costs. An energy savings ROI using the above example would be around 9.5 years," he wrote. "Now keep in mind that the type and thus price of the SSDs, along with size and quantity, will vary. Likewise, the number of HDDs being replaced will also differ. Thus, the ROI could be less with more HDDs being replaced. So there is an ROI, and it can in fact be down in the couple of years range, if not less, depending on the configuration."
Energy efficiency equals productivity
Ultimately, energy-efficient storage is just one tool companies can use to meet the demands of their business. "Keep in mind that there is no such thing as a data or information recession, so those energy savings for many environments are really going to be used for enabling organizations to grow and expand within a given footprint," Schulz said. While environmental issues are important, economic necessity also comes into play, as increasing amounts of data will require additional energy to operate IT resources. That kind of growth requires more efficient energy use in order to get more work done per watt of energy, he said.
"The challenge being faced most commonly is not the demand or requirement to address CO2 or other perceived green issues or even energy costs. The real challenge is supporting continued demand, which requires more physical resources (servers, storage, networking, workstations, monitors, etc.) in a given physical environment that also need to be cooled," Schulz said.