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9: Green IT Case Studies for Energy Utilities 153

♦ Six to 10 LPARS (including two VIO LPARS).
♦ Energy savings: The IBM pSeries Web sites give case studies of
more than 50 percent energy reduction consolidating stand-alone
pSeries servers onto pSeries virtual servers (LPARS).

Step 4. Evaluate Cooling
In July 2007, Variable Frequency Drives were installed for all the cooling
system blowers. There are 10 chillers, and they are powered down when not
needed (for example, when outside air in the winter is used for cooling).

Step 5. Manage and Measure
There is only one meter for the data center building. In addition to the
data center, the building includes some conference rooms and a few offices. It
is estimated that more than 80 percent of the electrical energy consumption
is due to the data center. The IT team plans to use Active Energy Manager
(AEM) to measure, monitor, and manage the energy components built into
the servers and other IT systems (see information in the “Next Steps for This
Energy Utility’s Green Data Centers” section). ptg
The main data center energy use versus the IT server and storage capacity
has been reduced due to server and storage virtualization and other technol-
ogy (including cooling and lighting, and so on) to increase efficiency. As
analysis of the energy use indicates, the KWH usage increased over three
years by two times due to data center consolidation, and such. However, the
IT team estimated that server capacity over the same period increased 4 to 5
times. Server capacity increase is not easy to determine, especially with vir-
®
tual servers and when there is a mix of x86, UNIX , and mainframe
machines. SPEC Marks discussed in Chapter 7, “The Need for Standard IT
Energy-Use Metrics,” do provide some comparison metrics, and this is an
area to be further explored. Chapter 7 also discusses the new SPEC informa-
tion being gathered on server power and performance, which will prove to be
useful for building green data centers.
KWH per month energy consumption at the main data center increased
from an average of 217K KWH in 2005 to an average of 555K KWH in
2008 (through 11/08). Thus, the average KWH per month at the main data
center increased approximately 2.5 times from 2005 through 2008. Server
capacity during that period increased by 4 to 5 times. There was a noticeable
peak in the KWH graph during September 2006, when the two large main-
frames were moved from the Ohio, data center to the main data center as the
final part of a data center consolidation project.