I've been doing some calculations on power usage of various items in the workplace, to see what takes the most energy away from your office.

One of my first investigations went towards focusing on the high consuming non-IT related equipment namely air conditioners, which are also used in server rooms and should also apply for them.
People tend to put the aircon on the highest(in winter) or lowest(in summer) temperatures the electronic thermalstat can take, which is a real energy waster.

I've noticed in our office environment people putting the thermalstat on 30 degrees celcius, which is more than the standard 21-23 degrees celcius which is normal "productive" conditions.

Something as simple as setting your aircon to 21-23 degrees already helps alot, not making the offices too warm and also helping with unneccesary flu or colds being generated int he office environment.

When you set it to 30 degrees the compressor of the airconditioner has too work permanently to reach the 30 degrees, which is almost impossible, if you take into account the temperature entering through opening doors and temperature coming through glass and walls.
Running on lower temperature causes the compressor of the airconditioner to actually rest for periods of time, thus saving time and energy in these times.

A 36 BTU aircon can pull around 18 Amps, thus coming to around 2500W/h which equals to R1.50(if R0.50/KWh) per hour to run 1 single aircon.

One can reduce this greatly by "somehow" programming aircons to have a maximum temperature of 24 degrees, which will stop employees setting it higher.

I'm still busy researching this topic with great interest as not only Server rooms can save energy but can also be extended to the whole enterprise.

I have not started on the server room equipment yet, but would be nice to see how one can save energy there.