[Beowulf] Academic sites: who pays for the electricity?
diep at xs4all.nl
Wed Feb 16 10:08:05 PST 2005
At 08:16 16-2-2005 -0800, David Mathog wrote:
>In most universities services like electricity, water, and
>A/C are paid for by the school. To do so they take "overhead"
>out of every grant. Partially as a consequence of this they
>typically have a very poor ability to meter usage on a room
>by room basis.
>Now somewhere between the 10 node Pentium II beowulf sitting on
>a lab bench and the 1000 node dual P4 Xeon beowulf in a machine
>room that takes up half the basement the cost of the electricity
>(both for power and A/C) goes from a minor expense to a major
>one. Really major. For instance, in that hypothetical large machine,
>at 10 cents per kilowatt hour (a round number), assuming 100 watts
>per CPU (another round number) that's:
> 1000 (nodes) *
> 2 (cpus/node) *
> .1 (kilowatts/cpu) *
> .1 (dollars/kilowatt-hour) *
> 365 (days /year) *
> 24 (hours/day) =
> 175200 dollars/year
Complete academic nonsense calculation. If you use quite some electricity
the electricity gets up to factor 20-40 cheaper. Getting a factor 10
reduction in usage bill is pretty easy if you negotiate properly.
However you must avoid starting machines at peaktimes. Big fines get given
for that. So it's cheaper to let them run 24 hours a day than to start them
in the morning after say 7 AM (depending upon local habits).
Please note that nothing beats the price of nuclear power
(as a member of the high voltage power forum i do not have an opinion on
Electricity production costs of nuclear power are hundreds of times cheaper
than producing it with oil, oil produces it roughly for 5 dollar cent a
kilowatt (if memory serves me well). Coals have a CO2 problem for nations
which are in Kyoto agreement (USA isn't), but also is nearly as cheap as
So the actual price they deliver huge power for to big institutes is a very
easy negotiation to get it factors down.
ex-member of high voltage powerline forum.
>The A/C expense is going to vary tremendously depending upon
>the outside temperature. It's going to be much higher for us
>in Southern California than for a site in Anchorage.
>"Typical" lab usage is widely variable but I'd be amazed
>if most biology or chemistry labs burn through even 1/10th this
>much for the equivalent lab area. Some physics lab running
>a tokamak might come close.
>Anyway, the question is, have any of the universities said "enough
>is enough" and started charging these electricity costs directly?
>If so, what did they use for a cutover level, where usage was
>"above and beyond" overhead?
>>From an economic perspective having electricity and A/C come out
>of overhead (without limit) grossly distorts the true cost
>of the project over time and can lead to choices which increase
>the total overall cost. For instance, the use of Xeons instead of
>Opterons has little effect on TCO if somebody else is picking
>up the electricity tab, but could change the power consumption
>significantly on a large project.
>mathog at caltech.edu
>Manager, Sequence Analysis Facility, Biology Division, Caltech
>Beowulf mailing list, Beowulf at beowulf.org
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