IT Data Center "Green" Myths and Realties
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
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
Myth: IT data centers produce 2% of all global carbon dioxide (CO2)
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
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
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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