Will Blog for Experience: Patrick

I'm a student blogger for Experience.com and if my blog gets the most readers out of these 5 blogs I will be going to Washington, D.C. for a job shadow at the Department of Energy, courtesy of CBCampus. Experience is a career site specifically for college students & alumni. They provide extraordinary job opportunities, real-world insights, and a network of inspirational role-models to help students explore and launch careers they love. Keep reading my blog if you want me to lead this challenge!

Experience, Inc.

Monday, January 01, 2007

Portable Solar Power for $180

For about $180, I brought together all the components needed to power a typical laptop for a couple hours solely on solar power. It's great for emergencies, or just knowing you are powering something real with a completely renewable resource.

This kit weighs about 2 lbs, costs $180, and will power my Macbook for 1.75 hours (1.83ghz, browsing the web and checking email via Airport Extreme, bluetooth off, screen brightness about 70%) with a little more than 5 hours of good sun. Here's what it takes:

Solar Panel

I bought my panel on ebay for $80. It's a 15 watt foldable panel, weighing 1.6 lbs with folded dimensions of 10.5" x 8.5" x .75". Easy to stuff in a backpack, to say the least. It outputs power via an SAE 2-prong trailer plug.

Sunlinq 25W Foldable Panel. The included accessory kit means you don't need to buy any more cables, but it's prohibitively expensive at $374
Build your own.


I like the Powerpacks offered by Xantrex, because they bundle a battery and an inverter into one package, meaning there are fewer cables to connect and it's easier to use. I got a Powersource Mobile for $95 from Amazon a couple weeks ago; they've since raised the price, but you can find it elsewhere for about the same. It weighs less than a pound, has a 4 amp hour lithium ion battery, with a three pronged AC outlet as well as two USB ports.

Better: Powerpack 600 HD. With 3 AC plugs, a built-in flashlight and radio, and a 28 A-hr battery, you can do a lot more with this. It only costs $130, but it weighs almost 30 lbs.
Cheaper: Xpower Pocket Power Pac 100. It's a little clunkier, but has a 3.3 A-hr NiMH battery and is almost as compact as the Powersource Mobile, for only $65.

CLA Adapter

To connect the solar panel to the battery, you're going to need an adapter to go from the 2-prong trailer plug to a cigarette lighter. You can buy it alone for about $5, or you can buy an accessory kit with a few other nice cables for $18.

Closing Thoughts

If you plan to let this sit for days on end, or plan to get a solar panel with more wattage than I had, I would highly recommend getting a charge controller to prevent damaging your battery.

Through trying this out, I found that it is very hard to get 5 hours of good sun in Chicago in the winter. It's a great feeling when it works, but not practical for day-to-day use.

While the folding panel itself is small, unfolded it's fairly large. The best places I found to lay it out were on a roof or in a park.

I would really like something even easier to use, such as a backpack with solar panels on it. Voltaic solar bags are close, but not really practical for powering a laptop. Yet.