Welcome to the MacNN Forums.

headbirth · May 1, 2006, 08:08 AM

Anyone know how many Volts/Watts it would take for a solar panel to charge a PowerBook (PPC or Intel)?

SLiMeX · May 1, 2006, 08:23 AM

I would only assume itsthe same as whatever it takes for the power adapter to charge your powerbook.

Tuoder · May 1, 2006, 10:23 AM

If you build a charger to connect directly to the battery, it is not a really big deal. But then, you would need a pretty darn big panel to do it. Trying to connect direct to the laptop is probably not a very good idea.

http://froogle.google.com/froogle_cl...mp;scoring=mrd

I think that would do the job. Unless, you are willing to wait a really long time for a charge. Even with this one, I think you would be waiting quite a bit when it isn't bright out.

headbirth · May 1, 2006, 11:07 AM

So, I would have to remove the battery and get a charging unit to plug the battery into for charging rather than plug the solar panel into the laptop?

Tuoder · 11:29 AM

Originally Posted by headbirth

So, I would have to remove the battery and get a charging unit to plug the battery into for charging rather than plug the solar panel into the laptop?

In a perfect world, you would build a DC-DC converter so as to make Solar Panel Voltage (variable)-->Charger Voltage (fixed). If there is a such thing as a PB battery charger, and I suspect that there is, you would just remove the transformer and hook up the output of the DC-DC converter to that. If it was nice and bright, you could theoretically charge at the same rate as the wall charger. But alas, it is not nearly always clear and bright.

(listed above) Solar Panel-->DC-DC converter-->Modified Battery Charger.

Another way to do it, without building much, would be this.

Solar Panel-->12v battery charger-->Car Battery-->12VDC to 120VAC inverter-->Regular laptop AC adapter

This has the advantage of more stable power output, and you can buy all of this stuff off of the shelf. Depending on the size of the panel and the capacity/quantity of car batteries you could have very stable output. This would be terribly expensive, however. Inverters can usually handle 10.6-14.4VDC and still put out 120VAC. You also don't have to worry as much about how many watts the panel is giving you at a given second. You just have to make sure that the Watt-hours in are greater than or equal to the amount the laptop uses in a day.