My work PC’s energy cost

posted in: education | 0

One of the tenets of Enclave Harbor is to help raise environmental awareness while teaching middle school kids a little “real life” science via virtual field trips.  It is fitting to look at the environmental costs of computer usage since we are using OpenSim on a dedicated server that is on 24/7.

Today a perfect opportunity arose to explore this on a personal level.

I use Defraggler regularly on my work and home computers. Today I updated to the latest version of Defraggler and it has a new “Health” tab (see below). I was intrigued at the total number of hours that my work machine has been powered on.

My work PC has been on for a total of 14,924 hours over the last five years. I am the second “owner” of this box and the only time I leave it on overnight is for Blender renders (time consuming 3D graphics and animations).

If this power supply runs at 500 watts that means the PC has used 7,462 kilowatt-hours of electricity during that time.

In the US, the average cost per kilowatt is 13.4 cents (June ’11 national average – double that for Hawai’i). It has cost my company $999.91 in electricity to power this computer over the last 5 years. That’s only to power the box and does not include the dual monitors or any servers I access for work files.

Let’s compare my machine’s ~$200 a year cost with two hypothetical scenarios – one in which the machine is on eight hours a day, five days a week for 50 weeks a year and one left on 24/7.

  • 8 hours X 5 days X 50 weeks = 2,000 hours or $134.00 a year in electricity
  • 24 hours X 7 days X 52 weeks = 8,736 hours or $585.31 a year

That is a difference of $451.31 in one year! Or 4.37 times more electricity!

If we extend these scenarios to a company with 300 employees then we would have a difference of $135,393.00 in one year!

The numbers speak for themselves.

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