[Power] Haiti power questions

[Richard A. Smith]

On 12/05/2010 12:05 AM, scott at solarnetone.org wrote:

>>
>> Assuming you are only going to 50% DoD I'm guessing your minimum battery
>> voltage is about 11.5 to 11.6V.
>
> 12.2 is the lowest I have seen my battery array drop in 5 years of
> operation.  That was during a weak but especially large and slow
> moving tropical storm a couple of years ago.

That would suggest that your normal DoD is much lower than 50%.  What 
average DoD did you design for?

I must have been looking at the wrong curve when I said 11.5-6 thats  a 
C/5 number rather than a C/20 or C/100.  12.2V is approx 50% on some of 
the generic curves I found on the web.

> either way... I spread it out over 24h, while you need it in a 3h span.
> That dictates a few changes to accomodate a slightly different load
> profile.  That being said, I will put together a parts list for an exact
> replication of the power system for you, and a list of parts slightly
> better tuned to the 50 XO load.

Thank you.  That way someone wanting to implement such a system has a 
starting point.  Each site is different and will need customisation for 
their specific workflow and geographical location.

Did you run any HOMER simulations for your existing setups?

What sort of logs do you have for the performance of the system  Do you 
log things like PV output or Wh consumed on a periodic basis?

It would be interesting to compare a HOMER simulation against real world 
data.

-- 
Richard A. Smith  <richard at laptop.org>
One Laptop per Child