PV Gap

Jo Said:

How many watts do you need to charge an average Cell Phone?

We Answered:

You really need to know voltage and current (which is watts - P=IE), but without sufficient voltage from the solar panel, you won't be able to create the potential difference (voltage) needed to cause current to flow to the battery.

My suggestion would be for you to look at your charger's parameters and then build a solar panel array with the same characteristics. As long as you have a high enough voltage, it will charge. The current generated will determine how long the charging will take.

The other thing you have to be careful of is charging NiMH and/or Lithium Ion batteries without cut off circuitry. "Smart Chargers" lower the voltage of the input as the battery starts to come to full charge. Although it is unlikely that you will generate enough current with a typical solar array, it is possible to cause the battery to explode if you don't have a step down/ shut off circuit in the charger...

Hope that helps. Good luck.

Cheryl Said:

Basic Solar Panel?

We Answered:

try checking out in goggle

Jeff Said:

Solar Panel wattage for my Electric Bike?

We Answered:

http://handybobsolar.wordpress.com/2009/…

google " northern tool " i am sure they sell world wide.

they have solar kits ,

they sell are a decades old industrial supply company that sell all things at cheap prices.

Jon Said:

I'm looking for small, portable solar powered camping/hiking stove. Not too expensive but works really well?

We Answered:

Though I have not used one myself I would trust any of these solar cooking products on this page from Real Goods (link below), the consumer product sales division of the Solar Institute in California.

http://www.realgoods.com/category/campin…

They test all of the items to assure that they work before offering them for sale. In fact, they are probably one of the best sources for all kinds of products and educational materials for alternative energy products. They have a lot of cool stuff for camping and back country use. I worked at a remote archaeology field camp several years ago and we used their hand-crank radios and solar showers as well as the flexible solar panels and inverter units to power laptops and instruments.

It is true that it would be very hard (if not impossible) to convert enough amps from a solar cell to cook by inductive or resistance heating BUT concentrating the sun's rays directly as these cookers do really does work. Organizations like the Peace Corps have been teaching people in underdeveloped areas to build and use solar cookers for decades to save local forests and reduce smoke and pollution. The process is different then just setting a pot on a fuel stove, however, and the units aren't cheap or terribly compact. You can build one yourself, similar to these, out of sheet metal and other materials.

Dana Said:

Can artifcial light, like say a flashlight, be used to charge a small solar battery?

We Answered:

Like the others have said... yes. But there is no such thing as a free lunch.

So you'd end up wasting a lot of extra energy from the artificial light source to charge up that battery. Best use a hand crank as the other answer put it. Or better yet, plan ahead and put the solar battery out in the sol (sun) ahead of time to charge it up to full capacity.

I have an iPhone recharger hanging out of the cigarette lighter socket in my car. A car I can drive to any camp site. Works like a charm. You can get one at any Apple Store.

Dennis Said:

What size portable (fold-up) solar panel will power a 110 volt AC battery charger.?

We Answered:

A 10w charger will require roughly 5 hours of light to recharge a D70 battery. Check out Sundance Solar for some great options.
But eh, why are you taking a $1000 electronic camera with NO weather sealing on a canoe trip? Dude!
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added: I tried to respond to your message but I'm not sure it got through. I'm afraid I can't answer your follow-up question. I briefly looked into solar for myself but eventually decided on a couple of spare batteries instead. This involved less expense and bulk.