[6039] in Release_7.7_team
Re: Fwd: Putting display to sleep on Athena
daemon@ATHENA.MIT.EDU (Jonathon Weiss)
Tue Jul 29 16:38:39 2008
Message-Id: <200807292038.m6TKc1r1000794@speaker-for-the-dead.mit.edu>
From: Jonathon Weiss <jweiss@MIT.EDU>
To: Jonathon Weiss <jweiss@MIT.EDU>
cc: Greg Hudson <ghudson@MIT.EDU>, William Cattey <wdc@MIT.EDU>,
release-team@MIT.EDU
In-reply-to: Your message of "Mon, 28 Jul 2008 18:15:23 EDT."
<200807282215.m6SMFN9x025891@speaker-for-the-dead.mit.edu>
Date: Tue, 29 Jul 2008 16:38:01 -0400
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This got me to thinking "this will probably save enough power to
actually be interesting, won't it?" to answer that question for
myself and other's I present some numbers.
Assume you can save 25W by sleeping an average Athena LCD monitor (I
beleive this is a conservative estimate, and the actual number will be
more like 30 or 35).
Multiply by 1000 Athena workstations (Actually 984 in the July status
report, but 1000 is really easy to multiply): 25kW
Assume that the average monitor will be sleeping 10 hours a day/night
(I think this is very conservative, especially since it assumes
weekends are regular days, but again it is easy to multiply): 250kWH
365 days/year: 91.25 MWH/year.
http://cogen.mit.edu/powermit/ estimates that N* bills MIT $58.77/MWH
(though this number appears to be 5 years old, and is probably a
low-ball estimate now): $5363/year
If we assume 35W savings and 14 hours a day of sleeping monitors
(which is certainly more agressive, but not unbelievable):
490kWH/day
178.85MWH/year
$10511/year
Realistically, I'd guess that we'll fall between the two. Either way,
it seems worth pursuing.
Jonathon
