As the use of HIT rises, so does the need to conserve it's direct and indirect costs: electricity and the unhealthy methods we produce it.

clipped from news.wired.com

A new report from the Environmental Protection Agency estimates that the easiest, least inexpensive changes to data center operations - involving tweaks to software, layout and air conditioning - could boost efficiency by 20 percent.

But even that level of improvement would still lead to higher overall electric use in the coming years. Going further, and actually reducing information-technology's strain on the electric grid, will require a more aggressive commitment. The EPA says 45 percent improvement - enough to lower electricity usage by 2011 - can be achieved with existing technologies.)

For example, almost all the energy that goes into the air conditioning systems is used to run giant chillers that make the air pumped through the rooms' raised floors a brisk 55 degrees or so, sometimes as low as the 40s. Such extremely cold air is blasted in to guarantee that no single server's temperature gets much above the optimum level, which is around 70 degrees.