This is the second half of a two-part article. You can find the first half here.
In order to cut down on costs and ensure that there is enough power, a close look at each individual component is requisite. The next step is to figure out how each component impacts the datacentre as a whole.
Steve Yellin, vice president of product marketing strategies at Aperture Technologies, a datacentre management software firm, says that managers need to consider four separate elements that contribute to overall datacentre efficiency - the chip, the server, the rack and the datacentre as a whole. Savings in any one of these components yields savings in each of the higher area above it.
"The big message is that people have to get away from thinking about pieces of the system," Stanford University's Koomey says. "When you start thinking about the whole system, then spending that $20 extra on a more-efficient power supply will save you money in the aggregate."
There are strategies for cutting power in each area Yellin outlined above. For example, multi-core processors with lower clock speeds reduce power at the processor level. And server virtualisation, better fans and high-efficiency power supplies - such as those certified by the 80 Plus programme - cut power utilisation at the server level.
Five years ago, the average power supply was operating at 60 percent to 70 percent efficiency, says Kent Dunn, partnerships director at PC power-management firm Verdiem and programme manager for 80 Plus. He says that each 80 Plus power supply will save datacentre operators about 130 to 140 kilowatt-hours of power per year.