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IT Data Center "Green" Myths and Realties

Greg Schulz

Is "green IT" a convenient or inconvenient truth or a legend? When it comes to green and virtual environments, there are plenty of myths and realities, some of which vary depending on market or industry focus, price band, and other factors. For example, there are lines of thinking that only ultralarge data centers are subject to PCFE-related (power, cooling, floorspace, environment) issues, or that all data centers need to be built along the Columbia River basin in Washington state, or that virtualization eliminates vendor lock-in, or that hardware is more expensive to power and cool than it is to buy. The following are some myths and realities as of today, some of which may be subject to change from reality to myth or from myth to reality as time progresses.

Myth: Green and PCFE issues are applicable only to large environments
Reality: I commonly hear that green IT applies only to the largest of companies. The reality is that PCFE issues or green topics are relevant to environments of all sizes, from the largest of enterprises to the small-medium business, to the remote office branch office, to the small office, home office or virtual office, all the way to the digital home and consumer.

Myth: All computer storage is the same, and powering disks off solves PCFE issues.
Reality: There are many different types of computer storage, with various performance, capacity, power consumption, and cost attributes. Although some storage can be powered off, other storage that is needed for online access does not lend itself to being powered off and on. For storage that needs to be always online and accessible, energy efficiency is achieved by doing more with less, that is, boosting performance and storing more data in a smaller footprint using less power.

Myth: Servers are the main consumer of electrical power in IT data centers.
Reality: In the typical IT data center, on average, 50% of electrical power is consumed by cooling, with the balance used for servers, storage, networking, and other aspects. However, in many environments, particularly processing or computation- intensive environments, servers in total (including power for cooling and to power the equipment) can be a major power draw.

Myth: IT data centers produce 2% of all global carbon dioxide (CO2) emissions.
Reality: This is perhaps true, given some creative accounting and marketing math. The reality is that in the United States, for example, IT data centers consume around 2–3% of electrical power (depending on when you read this), and less than 80% of all U.S. CO2 emissions are from electrical power generation, so the math does not quite add up. However, if no action is taken to improve IT data center energy efficiency, continued demand growth will shift IT power-related emissions from myth to reality.

Myth: Server consolidation with virtualization is a silver bullet to address PCFE issues.
Reality: Server virtualization for consolidation is only part of an overall solution that should be combined with other techniques, including lower power, faster and more energy-efficient servers, and improved data and storage management techniques.

Myth: Hardware costs more to power than to purchase.
Reality: Currently, for some low-cost servers, standalone disk storage, or entry-level networking switches and desktops, this may be true, particularly where energy costs are excessively high and the devices are kept and used continually for three to five years. A general rule of thumb is that the actual cost of most IT hardware will be a fraction of the price of associated management and software tool costs plus facilities and cooling costs.

Regarding this last myth, for the more commonly deployed external storage systems across all price bands and categories, generally speaking, except for extremely inefficient and hot-running legacy equipment, the reality is that it is still cheaper to power the equipment than to buy it. Having said that, there are some qualifiers that should also be used as key indicators to keep the equation balanced. These qualifiers include the acquisition cost; the cost, if any, for new, expanded, or remodeled habitats or space to house the equipment; the price of energy in a given region, including surcharges, as well as cooling, length of time, and continuous time the device will be used.

For larger businesses, IT equipment in general still costs more to purchase than to power, particularly with newer, more energy-efficient devices. However, given rising energy prices, or the need to build new facilities, this could change moving forward, particularly if a move toward energy efficiency is not undertaken.

There are many variables when purchasing hardware, including acquisition cost, the energy efficiency of the device, power and cooling costs for a given location and habitat, and facilities costs. For example, if a new storage solution is purchased for $100,000, yet new habitat or facilities must be built for three to five times the cost of the equipment, those costs must be figured into the purchase cost. Likewise, if the price of a storage solution decreases dramatically, but the device consumes a lot of electrical power and needs a large cooling capacity while operating in a region with expensive electricity costs, that, too, will change the equation and the potential reality of the myth. ♦

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This book presents virtually all critical IT technologies and techniques to discuss the interdependencies that need to be supported to enable a dynamic, energy-efficient, economical, and environmentally-friendly green IT data center.

About the Author

Greg Schulz is founder of the Server and StorageIO group (StorageIO), an independent IT industry advisory consultancy firm. He is the author of the books Cloud and Virtual Data Storage Networking, The Green and Virtual Data Center, and Resilient Storage Networks. He is a popular blogger and also a fixture on Twitter.