[Soekris] solar power

[Poul-Henning Kamp]

In message <8A1DA40786CE4741850C0AF80F2D5256CA4511 at idealab.printperpage.com>, "
Robert Woodcock" writes:

>The battery can't reach a float voltage higher than the open-circuit
>voltage of the solar cells. As long as this voltage is lower than that
>at which the battery starts to vent, it'll be ok. As I said, if he
>winds up getting an array with an open-circuit voltage above what the
>battery can safely float at, he can get a controller.

You can't get any panels of the necessary size with an open-circuit
voltage of 13.8V.

>> 2.  You vastly overestimate the geometric efficiency of the solar cels.
>
>You wrote, "At my lattitude, 56N, to produce 100W in best case
>illumination you need about one square meter of solar panel."
>
>My estimate was actually a fair bit more conservative.

>From the same panel you may get 4W in clear sun in December.  Your
estimate was far more optimistic :-)

>
>> Solar panel   ----+----|>| ----------------+--------  Soekris
>>                   |                        | 
>>                charge controller ---|>|----+
>>		   |
>>		   |
>>		battery
>>		   |
>>              ----+--------------------------------- GND
>
>You're implying that there's a ground connection for the solar
>panel, Soekris, and charge controller, right?

Yes.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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