Everyone wants to be responsible about their energy consumption, and while from a corporate perspective, it looks great in press releases and marketing materials, it's a hard direction to move in if you can't justify the expense in an objective manner.
So how do you establish the actual return on investment for your energy optimization projects?
The most obvious method, and the best place to start, is by having an objective baseline of your current energy costs related to IT. Make sure not just to include desktop computers and monitors, but any associated peripherals. Include the networked and personal printers. Include the Blackberries and cellphones because of their chargers. How about scanners? Air-conditioning? UPS and power management systems also have a draw and should be measured. Network gear, KVM switches, and the list can go on. For an extensive list contact Tsunami.ca for our whitepaper on Green IT. This audit can take some time (and therefore money), particularly if you don't have a CMDB (Configuration Management Database) in place already.
Incidentally, if you do have a CMDB, or are currently undertaking a CMDB project, have you included energy consumption rates as a CI (Configuration Item)? It's worth thinking about...
Once you have your baseline, you can now consider what initiatives your organization may undertake. Budget the cost of implementing those items, processes, or technologies (and are those costs that can be partially absorbed by budgets other than IT? ) and look at the energy reduction rates to calculate the initial, high-level ROI for the project.
But there's other ways to reduce those costs. In the Province of BC, BC Hydro has joint rebate programs with the Provincial Government that can make significant additions to your ROI calculations. If you are reading this from a location other than British Columbia the odds are that some similar rebates may be available for you as well.