[Server-devel] location and muscle of the school server

[Yama Ploskonka]

600 W is a lot.

I believe a lot of this is lost when converting AC/DC.

The AC-DC power converter for the computers is very wasteful.  Most 
alternative power sources (solar, wind) output DC, which can be stored 
in batteries.  When converting this DC to AC to feed the computers we 
have a loss, and another loss (as heat - that's why power sources need 
fans...) when going back to DC for the MOBO with a conventional power 
source.

Now, if we could cut the middleman out...

What we'd need is a converter that could take standard 12 V from the 
battery pile, and output the usual +12, -12, +5 - 5 and feed that 
straight into the MOBO.  Apparently it should be rather simple, but 
again, beyond _my_ ability.  Hope there's takers that can solve this.  I 
for one would want to build something like it if I knew how.

Yama


Tony Pearson wrote:
<snip>
 > In the case of OLPC Nepal, we will have three PCs (Proxy, School, and 
Backup) server.
 > That would be 600W, but we plan to support 150-200 students, so now 
on a student basis, is
 > only 3-4W per student.

 > internet connectivity is also uncertain.  We are trying to have a 
working system even one that
 > is useful/usable if the connection to the internet is down.

Hear, hear!  In my view, the internet will be mostly down... :-(

 > An interesting blog post I saw were "PlayPumps"
 > (http://blog.guykawasaki.com/2008/02/the-cleverest-i.html) where kids 
playground equipment
 > is used to pump water.  Perhaps this idea could be modified to 
generate and store electricity
 > into car batteries.  Many sustainable sources of energy like wind and 
solar can also be used.

Nepal - mountains - mountain streams - water energy?

In my notions for Bolivia I expect to depend on water energy in some areas.