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The Greening of IT
78 How Companies Can Make a Difference for the Environment

computer-room air conditioners (CRACs) have variable-speed fans and can
adjust dynamically to their data center environments. Alternative cooling
approaches, including ice storage and geothermal energy, accept the heat and
focus directly on reducing the cost of cooling the data center. Reducing cool-
ing loads gets the attention of utilities because their summer peak demand
periods are caused by air conditioning. Pacific Gas and Electric Company is
offering $1,000 rebates to customers who buy efficient servers that generate
less heat.
Utilities also offer incentive programs for virtualization, which reduce the
number of physical servers required. Virtualization is not new, but vendors
are strongly promoting it now that energy costs are of concern.
Virtualization, the representation of physical resources with logical ones, has
also matured and can simplify IT while saving costs. As emphasized through-
out this book, virtualization is one of the most effective tools for more cost-
effective, greener computing. By dividing each server into multiple virtual
machines that run different applications, companies can increase their server-
utilization rates and shrink their sprawling farms. Virtualization can also
extend to the network and storage, again eliminating energy-drawing equip-
ptg
ment from the data center, while more efficiently utilizing the remaining
equipment. Virtualization is so energy-friendly that PG&E offers rebates of
$300 to $600 for each server that companies eliminate using Sun or VMware
virtualization products, with a maximum rebate of $4 million or 50% of the
project’s cost, whichever is less. Virtualization is also a key technology in
qualifying for Energy-Efficiency Certificates, issued by Neuwing Energy
ventures.
The actual rebate for a smaller company might, of course, be far more
modest and might not drive a virtualization project’s return on investment.
For example, Swinerton Construction estimated it would get a $3,200 rebate
from PG&E when it implemented VMware virtual machines, but it ended up
with only $800 after PG&E completed complicated calculations for power
use. Still, the project saved the company more than $140,000 in 2008, if you
subtract the cost of servers it hasn’t had to buy, as well as more than $50,000
saved on power and cooling.

Energy-Efficiency Ratings for IT

Electric utilities need to base their rebates on proven, measurable ways to
save energy in the data center. Tools such as IBM’s Active Energy Manager