15/2/10 NOTE: this post has content that is seen as inaccurate by Miserware and you are advised to read all the text before forming conclusions to give Miserware a fair hearing.
Interested by some of Alan’s posts at the Open Sourcerer, I’ve been conducting an experiment in recent weeks with the Miserware power saving software that claims to save energy by better controlling CPU management. I run a new (late 2009) pc with an Intel Core 2 Quad Q8200 (4x 2.33) CPU with a 450w PowerCool 80+, and have given it a go. However, I didnt rely on the software’s own claimed power savings, I put an electric meter between the PC’s plug and the socket, and directly measured the power usage over 3 weeks, both with and without the software installed, set at my current domestic electricity rate pkwh.
Here is my data:
|miserware installed?||date||£ of electricity used||£ per day from last reading||£ per day||annual cost||annual saving|
|no||19/01/10 14:00||0||pc booted up|
|no||23/01/10 22:00||0.62||0.1453||0.1431||52.22||miserware installed|
|yes||08/02/10 08:33||2.81||0.1423||0.1418||51.77||Uninstalled 8 feb|
|no||13/02/10 05:12||3.53||0.1481||0.1481||54.07||2.3||test stopped|
What I did was to run the PC without the software installed for 4 days from 19-23 Jan, installed miserware from 23 Jan to 8 Feb, then ran the PC again from 8 Feb until today. Congratulations to the miserware support though, when I had issues installing they were right on the ball, and FOC.
The results are pretty unimpressive. Despite a claimed 15% power saving claimed by the software (sudo grep Estimated energy /var/log/* ) it actually made very little difference at all. In fact, if you average out the estimated annual usage for the 2 periods without running miserware ((52.22+54.07)/2) = 53.15 and compare that to the annual cost running miserware of £51.77, you see a 2.7% power saving thats worth about £2.30 a year. OK, its a saving, but its not worth a lot to me.
The scary observation is that if you leave a PC on 24/7, its going to cost you over fifty quid a year at current online dual fuel electricity tariff rates!