User talk:Ccarrick/Power Generation
 Human power generation
Since the XO battery will only recharge so fast, it seems to take about 2 hours to charge one, no matter what the wattage is available.
So, even if it induces it own inefficiencies, wouldn't it make sense for a human-powered charging station to charge a larger storage battery, which could sink power faster, and then use that battery to charge XOs.
Humans on bikes can produce (IIRC, someone check this) on the order of 150W for longish periods. A charging station could be made from a hacked bicycle spinning a salvaged auto alternator and an auto storage battery.
My first guess is that there would be enough energy produced to recharge an XO in about 1/2 hour of pedaling.
Rmyers 14:44, 26 May 2008 (EDT)
More on bicycle power generation. I set out to try to document my assertion of 150w and found something interesting. Windstream Power makes a bicycle powered generator. From its price, ($595) it is definitely a 'first world' solution. However it may be interesting to get one as a baseline to see how close a homebrew made from available materials could be made to perform.
A couple of interesting quotes from their website:
"The average person can expect to produce about 150 watts continously (sic) with the Human Power Trainer." Aha!
"While it is possible to directly power some DC appliances such as water pumps, the Human Power Trainer is primarily designed to charge a deep cycle, 12-Volt battery or to contribute to a 12 Volt battery bank. ... Certain DC appliances, such as DC lights, can be powered directly, but it is important to observe maximum voltage ratings to avoid damaging these appliances." Double Aha!
The site has a nice photo of a well spiffed-out bike rider with his racing bike on the 'Human Power Trainer', with it powering a laptop on a stand that he's watching. Maybe we should make one with a junker, homebrew trainer and a XO. The rider wouldn't have to pedal as hard :-)
Rmyers 16:15, 27 May 2008 (EDT)
 Human Power Generation
Thanks for the advice Robert. I completely agree about charging a separate battery to reduce the charge times for the XO. I have a few contacts from a Guatemala organization called MayaPedal that does a lot of work on using bicycle powered generators to run a range of appliances in the 3rd world and I'll see what systems they've developed.