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9: Green IT Case Studies for Energy Utilities 151

Along with discussing energy-efficiency best practices with IT vendors
and other IT groups, another important early step is to evaluate current
server and storage energy efficiency. The energy utility had already been fol-
lowing the standard best practices to provide cost-savings at their data cen-
ters, for example, with data center consolidation and server consolidation and
virtualization. Those best practices for data center cost reduction are also best
practices for energy efficiency.
Server refresh on a typical four-year basis was used to upgrade to virtual
servers. The server refresh program had already been underway for two years
® ®
with new IBM xSeries (x86) and pSeries (Unix) servers, all of which were
enabled for virtualization. The virtualization technology used for the x86
servers was VMware. The pSeries servers were virtualized using LPARS (logi-
cal partitions) with micropartitioning technology that allows the CPU
resource to be dynamically allocated among the LPARS based on computa-
tion need. The main data center was also refreshing servers using blade
®
servers. In addition to the virtual and blade servers, there were two zSeries
mainframes. The mainframes were moved to the main data center during a
data center consolidation project that eliminated the need for a large data
ptg
center in Ohio. There were also hundreds of legacy stand-alone servers at the
main data center that were not yet consolidated.
The storage technology at the data center also followed best practices for
energy efficiency. All the newer servers use Storage Area Network (SAN)
external disk storage under a SAN Volume Controller (SVC) that allows stor-
age virtualization. Tier 1 SAN storage is provided by an IBM DS8300 (90
terabytes). A new DS4800 is now under the SVC. The DS4800 replaces the
older IBM DS4500 and DS4400 devices via the storage refresh program. The
strategy calls for a three-tier approach for data storage for optimum perform-
ance and cost effectiveness.
At the main data center, the raised floor area is approximately 9,600 SF.
The tape area is approximately 4,000 SF, and the mechanical area (UPS, air
handlers, and such) is approximately 9,000 SF. The data center is considered
the raised floor—approximately 10,000 SF. There are also conference rooms
and office area at the main data center. The customer facilities manager
estimates that 80 percent of the annual energy consumption is for the data
center.

Step 2. Build
The 20-year-old Uninterruptible Power Supply (UPS) has been replaced
by building an addition to the current data center building (using the cur-
rent tornado proof construction with very thick walls and protected roof).