RE: Re: Effects of heat on Servers

["Paul Gale" <groups@xxxxxxx>]

Air con is either on or off for standard units - BUT 'Inverters' as I have
actually vary the output depending on the need i.e. my unit varies from
something like 0.5kW up to 4kW. This makes it far more economical to run
:-)

Paul.



-----Original Message-----
From: David Buckley [mailto:db@xxxxxxx]
Sent: 05 September 2003 10:18
To: ukha_d@xxxxxxx
Subject: [ukha_d] Re: Effects of heat on Servers



--- In ukha_d@xxxxxxx, Johan Olde <johan.olde@p...> wrote:
>
> While on the subject. I have a server room that is kept at 18
degrees
> constantly by the aircon. I've been trying to find out the
approximate
> energy cost when adding a server. If the server is using, say 300
watts,
> what would be the approximate energy consumption by the aircon to
> keep the temperature.
>
> I've asked a lot of people about this, but noone seems to be able
to answer
> this in a believable way, which makes me wonder if it isn't that
simple..

It is (in practice) that simple.

About a third.  So an additional 300w of computer load will increase
the aircon consumption by 100w.  Note that this isnt the nameplate
amount of aircon needed, but what the aircon will use in electricity
to move the heat.  The nameplate rating needs to be capable of the
extra 300w.  And also we are talking about averages here, as in
reality the aircon's compressor(s) are either on or off.  The
additional load makes the on/off ratio longer on the "on" side.

Computing equipment is, for all HVAC intents and purposes, expensive
fan heating.  It takes electricity in, and gives heat out.  The
energy supplied that is not converted to heat is trivial and can
safely be ignored.

I'd also suggest that 18C is too enthusiastic a temperature; 21C is
plenty cool enough, and will save considerable dosh.

Finally, if you have way to much air conditioning, it will add a
baseline cost to the real work done, simply by the fact its got
unnecessarily big fans.