Portable Solar Charging System for Netbook or USB
There was a thread over on the Survival Kit area that I'm moving over here because it seems more suitable.
I have used solar, extensively. On my second bike trip I installed a small solar panel in the front-right pannier box which trickle-charged a 6 Volt Lantern-flashlight sized Gel-Cel battery.
Portable solar is disappointing every time; but is a necessary evil sometimes.
Know that solar needs to be aimed almost directly at the sun. Aim it even a few degrees away and the current goes way down.
If the sun is covered even a little bit by clouds, the charging current goes down to almost nothing.
And, if you live in the incredibly baking heat of Arizona, they heat up which reduces their efficiency. Ironic.
Thus, portable solar panels are even worse than fixed solar panels. They tend to sag, which causes there to be lots less charging current.
In my case I have made an adjustable-degree solar panel holder on the top of my bicycle trailer using PVC pipe. Yes it is big and bulky-looking but the panel stretches out and attaches to the PVC rack with Lag pins so it is tense and taut. The PVC rack weighs almost nothing that way, and lets me charge from the panel both as I ride, and after I stop for the day. People tend not to laugh because it's really quite amazing (and it actually WORKS).
However, know that you will NEVER get from a solar panel anywhere near what they say you should so buy a solar panel that is WAY bigger than you need. You'll be lucky if you get half what they call the solar panel. My 26 Watt panel probably gives more like half-that in reality. A netbook generally sucks about 25 watts, and can settle down to about 15 watts if you have a Pixel Qi screen and turn off the backlight for outdoor use, are running Windows XP, have chosen to disable the faster speed on your Netbook (my Lenovo has two possible running speeds setable by your Power Saver settings).
I charge a netbook from a solar panel. This is near-to-impossible because of the way they build netbooks. Why? Well, most netbooks will shut down and won't even start to charge if the input current that the netbook needs at all moments is not being supplied.
I have a Lenovo with a Pixel Qi screen so it can be used outdoors. I had to install the Pixel Qi screen myself, though.
http://netbooked.net/images/sized/im...vo-600x387.jpg
The screen is about as expensive as the netbook, though.
http://laptops.techfresh.net/wp-cont...qi-display.jpg
It will only fit into two different Netbooks, perfectly. The problem is the way to turn the backlight on-and-off. Only certain netbooks will take that exact screen and at the same time have a keyboard command which turns off the backlight. The S-10 Lenovo IdeaPad does that. I installed it with Windows XP Professional instead of Windows 7 because it runs 25 percent more effiecient if you do that.
You can get it to work with a solar panel by doing two things.
You need to not charge the netbook's battery, you need to bucket charge Energizer "Energi to Go" which is a rather remarkable 20 Volt battery.
http://content.costco.com/Images/Con...uct/333246.jpg
In order to charge a 20 Volt Battery from a solar panel, you must use a Buck/Boost Power Supply.
I use another amazing little contraption called a "Dimension Engineering AnyVolt 3". The picture makes it look big, but it's really very tiny.
http://www.trossenrobotics.com/store...&bw=130&bh=130
It converts the X-to-19 Volts from the Solar Panel into a perfect 20 Volts.
You can't charge the battery with the netbook plugged-in to the battery. You charge the battery, then plug the netbook into it once it's charged.
The Energi-to-Go is amazing because it has three outputs. It has a 20 Volt output, a 5 Volt USB output, and a 12 Volt output.
So, it is the perfect battery to take camping no matter what you want it to power.
For a solar panel I use a Brunton Solaris 26 Watt (Which ranges around $450), but I also have a much smaller SunLinq 12 Watt foldable panel.
http://www.moontrail.com/details/bru...ris-26-mdl.jpg
(not picture of me)
The SunLinq has this annoying 15 volt regulator built-in. I yanked the regulator from inside the control box and diverted the voltage around the cheap voltage regulator. Brunton panels don't have a stupid regulator, so I'd suggest you buy them instead.
Brunton has one connector that plugs right into the "Energi to Go" battery to charge it... but of course it won't charge unless you bring the 12 volt voltage up to 20 volts with the Buck/Boost supply so put the buck/boost supply into a tiny project box along with a power connector in and out and you'll be able to charge anything. The connector has a 5.5 mm outside diameter. I buy my power connectors for it from Frys Electronics (right up the street).
For those who don't know, a Dimension Engineering AnyVolt 3 Buck/Boost power supply works almost like magic. You give it any input voltage from 5 volts to 30 volts (a solar panel) and you can set the output voltage to be anything from 3 volts to 24 Volts (perfect for solar panel enthusiasts who want to charge 24 Volt battery banks from a single 12 Volt panel).
Buck/Boost is magic because that means that, even if the input voltage drops to as little as 5 volts... the output will still be 20 volts (or whatever voltage you set for it).
What? Yep. "Once the output voltage is set, it does not matter whether input voltage is higher, lower, or the same as the desired output."
So, if the sun comes out and the voltage from the panel soars to 25 volts, the output is still 20 volts (or whatever you have it set at from 3 to 24 volts). Thus, the Buck/Boost will take any output as long as it is greater than 3 Volts and will then convert that to a very steady 20 volts no matter if the sun goes in, or comes out super-strong. If you have at least 3 Volts, you'll get SOME charging current. Try doing that with any other setup and see what you get.
As far as the "Energizer Energi-to-Go"...
The 5 Volt USB output is perfect to power an iPod, or any other thing which runs off a USB connector.
The 12 Volt output is perfect for anythng which can run off a car battery. It has a green connector that's a different size than the 20 volt output so you can't get them confused). It also comes with about 20 adapters so you can convert just the 12 or 20 volt outputs to just about any adapter. Many sites say that you can order any plug from Energizer, but mine CAME WITH about 20 converter adapters even though that wasn't even advertized.
The 20 Volt output is perfect for running most Netbooks or Laptops for at least an hour, just check to make sure that your power box to your laptop or netbook says 20 volts (used in conjunction with a fully-charged netbook you can get 4 more hours out of your netbook use if you minimize things like your LCD backlight with a Pixel Qi screen).
The disadvantage is that you lose a certain percentage of your power. The AnyVolt 3 is about 89 percent efficient. That's amazing, seeing all the benefits it gives to the portable-solar panel user.
The Energi-to-Go is 7 inches long, 4 1/4" wide and 3/4" deep. I sewed a zipper pouch I got at Home Depot to the side of my Nylon CaseLogic netbook case where I store it. I stuff the short converter cable which goes from the Energi-to-Go to the Netbook in the front zipper compartment.
An amazing mouse that goes with it well is a Kensington "Wireless Mouse for Netbooks" P/N K72345.
http://www.geardiary.com/wp-content/...on-mouse-2.jpg
The connector that plugs into the USB port is so short that I keep it plugged in all-the-time. The mouse has an on/off switch which is easy to remember to shut off. The mouse is very tiny, but works as good as a big mouse. It's 1 3/4" at its widest, 1 5/8" at the narrowest, 3 3/8" long and 1 3/8" tall. It feels like it fits a netbook.
And there you go, a netbook system that's small enough to go camping, that can be charged up from the sun (in reality), that can be viewed in full sunlight, and that can be used for double the number of hours that you normally can use a netbook.
