Re: Cost Justifications

[Vern Hamberg <vhamberg@xxxxxxxxxxx>]

Evan

This has nothing to do with CPUs of one manufacturer or another, it is a 
constant ratio for input (linear function) as watts and output as BTUs 
(heat). You can go to

     
http://www.unitconversion.org/power/watts-to-btus-it--per-hour-conversion.html

and plug in your own numbers - 1000 W == 3412+ BTU (British Thermal 
Units) in that calculator.

At least that's how I understood Larry when he said "it's a straight 
line relationship between input power and output heat"

Vern

On 3/9/2011 2:45 PM, Evan Harris wrote:
> Thanks for such a cool (pun intended) answer to what was a just a
> little bit of a tongue in cheek question.
>
> Reading your answer, I have another question:
>
> The figure you quote of 3413 BTU per input KW - is this dependent on
> anything else ?
>
> What I am really wondering is: is there any difference between intel
> vs power architectures - does one generate more heat than another ? Or
> are the differences in heat really about the multitude of boxes that
> tend to accumulate round Windows/intel applications ?
>
> If I ran an 8 way dell server with all my windows applications
> virtualised would it run hotter or colder than an 8 way power box all
> other things being equal ? Assume for instance that they are both
> using the same IBM SAN for storage.
>
> Thanks for taking the time with the previous answer .
>
> On Thu, Mar 10, 2011 at 3:03 AM, DrFranken<midrange@xxxxxxxxxxxx>  wrote:
> > OK I wrote a certification question on the ratio between input power and
> > output heat and got booed off the stage. SO I will simply tell you the
> > answer. For each KW of input power (1000 Watts) you will get 3413 BTU of
> > heat output. Now since a teeny tiny little bit of that 1000 watts went
> > into creating LED light (a VERY teeny bit) and some into noise generated
> > by the fans you might get a measly 3410 BTU of heat.  Point is that it's
> > a straight line relationship between input power and output heat.  It's
> > fairly common for HVAC guys who know there stuff to ask what the total
> > power input to the data center is, what the percentage load on the UPS
> > is, and use that number as a basis for calculating cooling requirements.
> > If you put 100KVA IN you will need to get 341,300 BTU out somehow.
> >
> > Now how much electricity it takes to remove those BTUs can vary A LOT.
> > In very cold climates, outdoor air can be drawn through filters to cool
> > the place (devices called 'economizers') and that's cheap. In hot
> > climates very large amounts of A/C are used to cool such rooms and that
> > cost can rival the power of the systems being cooled.  In the FrankenLab
> > from about October through March 100% of the heat generated is turned
> > into domestic hot water and then heat for the house.  In the summer it
> > ends up in the swimming pool or down a dry well. Very economical indeed.
> >
> >      - Larry 'DrFranken' Bolhuis