[Power] Good day for a solar panel test

[Stan. SWAN]

Nicholas et.al: Nice to hear of this development & indeed I'd like to see
some pix,dimensions & prices! That Voc 18V, 1.140A Isc looks to make it
~15W @12V?

Since my ~2008 (?) OLPC powering reflections the global photovoltaic market
has of course experienced a MOST satisfactory pricing reduction, & it's
quite common now to see poly & mono X panels in this 10-20W range retailing
for ~US$3-$4 a Watt. Here in Wellington (NZ) crowds such as Jaycar &
boating outfits seem to be slashing PV prices almost daily! Typical is this
20W mono for ÑZ$100  (~US$80)=>
http://www.jaycar.co.nz/productView.asp?ID=ZM9094&keywords=mono+solar+panel&form=KEYWORD
Back in 2007-2008 I paid ~ 3 times this price for a 20W polyX ....

Of course many of these PVs are rigid types & flexible panels still command
quite a price premium for their convenience.One pays for such packaging
rather than the energy resource...

That "short cord" (just HOW short?) comment may indeed be an issue,as many
setups have solar resources 5m or so away from the most convenient user
position. PVs are pretty rugged (& being cheaper now are less likely to be
stolen), but if users/OLPCs need to  outside for charging then a risk
arises of equipment theft & passing traffic/animal/weather damage etc. At
~1 Amp current the voltage drop along a somewhat longer (& suitable guage)
cable is pretty tolerable after all- it's not as if you are doing arc
welding!

    I await your  further insights & "tutu" awards !    Regards- Stan.
===================================================================

On 8 July 2012 16:49, Nicholas <independentcommercial at gmail.com> wrote:

> Received the new prototype OLPC panel today!
>
> First impressions--nice
> Well made, is a bi-fold 36 cell polycrystalline panel with a stiff
> nylon? -type backing. It's stiffer and shinier than the cordura I've
> seen. Looks quite rugged. It has a built-in OLPC power connector and a
> small mesh bag to wrap the cable in to for safe keeping. First thing
> to note is the power cable is short but it is not far from an ideal
> length IMO. Too long is a pain I've found in the past. However, it is
> an unprotected AWG22 cable which I fear will too easily damage;
> perhaps not, just an initial observation. Will do a high resolution
> photo of the panel surface to see how the lamination survives after
> some time in the sun. Will post it somewhere for safe-keeping. I've
> found with other panels with black fabric backing bubbles can develop
> in the laminate after some time in the sun.
>
> Initial measurements open-circuit 18v, 1.140A Isc (short circuit
> current). So, pretty good initial output without a load. It's mid
> Winter here and today is sunny with high cloud. It's not particularly
> warm.
>
> Will post current output on 10,20,30 and 40 ohm power resistors later
> on today if I get a chance.
>
> Many thanks Richard--you rule!
>
> For those on the OLPC NZ list, please let me know if you want to have
> a tutu, I will make a list or you can pass it around amongst
> yourselves. I would particularly like to see it go to the testing
> crowd that meets at that Auckland pub on the weekend. Also CC'd in
> this email Stan Swan who did some neat photos for the original solar
> olpc page if he wants a tutu too!
>
> All the best, Nicholas
>



-- 
------------------------------------------------------------------------------------------------------------

Stan. SWAN - Educator/writer.     EMAIL: => stan.swan at gmail.com
CELL:  (64)-021-672-958      HOME: (64)-(4)-562-7494     GST Reg: 36-921-021
POSTAL:  24 Tuatoru St,  Eastbourne-L.H.,  Wellington 5013,  NEW ZEALAND.
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