[Power] Power solutions for charging 150+ XOs1.0/1.5

[scott]

I must recommend solar for this.  Generators can easily become untenable 
if the supply line providing fuel is interrupted, notwithstanding the 
pollution and maintenence issues.

On Tue, 28 May 2013, Richard Smith wrote:

> On Tue, May 28, 2013 at 4:52 AM, Xavier Carcelle
> <xavier.carcelle at gmail.com> wrote:
>>
>> Can you recall us :
>> -the max current needed during the charge (and probably higher at the
>> beginning of the charge) ?
>
> Are you talking @ 240Vac? or at DC?
>
>> -the difference of current needed for 1.0 and 1.5 ?
>
> For 240Vac see the numbers I gave for George's SF presentation.
>
> https://docs.google.com/presentation/d/1HL2Ok_9E6VIzEh0G-d_iQ5RoSAtwMZ74pw_Nme84Dbg/edit#slide=id.g22073e4d_0_0
>
> Basically if you allocate a peak of 30W per XO (all XOs) you should be
> ok.  If you know it would only be XO-1 on the circuit then you could
> plan for 21W/XO.   Then 30Wh of energy for the full charge. XO off. If
> the XO is powered on then its a bit harder to come up with the energy
> needed because it depends on workload but it would be at least 15Wh
> more and probably closer to 20Wh.
>
>> -what the recommandations regarding the diesel group for 50, 100, 150
>> XOs to recharge at the same time during the XOs class ?
>
> I'm not clear on what recommendations you want.  You want
> recommendations for a Diesel generator or for a replacement of the
> generator with another technology?
>
>> PS : Of course you guys have seen the fast recharge process found by Eesha Khare
>> http://www.policymic.com/articles/43337/supercapacitor-phone-charger-eesha-khare-s-invention-charges-phones-instantly
>
> Not to be cynical but I would not hold your breath.  Various people
> have sent me articles about this and none of them actually say what
> this magic is.  Considering the only thing she has powered so far is
> an LED its a long ways off from any sort of usable product even if it
> really is some revolutionary device.  LEDs take mW and a device like a
> cell phone or batteries deal in Watts.  Thats 3 orders of magnitude of
> difference.
>
> --
> Richard A. Smith
> One Laptop per Child
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