While I wait for the Fez Spider to get back in stock (and some other modules to get here from HK), all I can do is think about what I want to build and how I want to build it, so power is my current thought and I was wondering if anyone can suggest a solar panel / battery system that will work nicely with the Fez Spider? It doesn’t need 7x24 capability, just nice POC capabilities.
Thanks
Blake
Eric aka ransomhall has a nice setup for Panda. Check his blog:
Adafruit’s solar LiPo charger [url]http://www.adafruit.com/products/390[/url] is really sweet. You can adjust the charge rate up to 1A with a resistor. It’s very popular, so they’re having a hard time keeping it in stock. Get on the ‘notified when back in stock’ list, and snag one quickly when they do show up.
I combined this with a MintyBoost, the large 3.7W panel they sell, and a 6600mAH battery to make the “Sol Booster” [url]http://www.ransomhall.com/Pages/solbooster.aspx[/url] and am able to run my FEZ Panda2 in sunny weather as long as I get the average “active” current draw under 300mA or so. I hibernate the board when not actively taking sensor readings to keep power consumption as low as possible.
Unfortunately, LiPo batteries do not like cold weather (under 0C) and I live in Vermont, so my outdoor solar experiments are in hibernation for the winter. I’m going to redesign the booster enclosure and circuit to “ruggedize” it for a spring debut of v2.
@ architect - thanks for the plug.
That looks very workable Eric, so I have my name on the notify lists for parts and it should have enough jam to run a handful of gadgeteer modules including a wifi module. For testing perhaps the 5V 2A plug would be a good idea (solar doesn’t work so good in my office:)). It looks like I’ll have to accept and embrace the concept of making nice cases like yours as that really puts a classy finishing touch on the project.
Thanks
As far as the ‘fancy case’ goes, I was on a shiny acrylic kick this summer. A friend pointed out that regular acrylic like this gets brittle with exposure to UV over time. There is UV resistant acrylic but it’s really pricey. So yes, it looks nice, but you may be better off with another material like bamboo. Check out this project http://www.bootstrapsolar.com , which is a modified version of the same circuit (more capacity to do two usb gadgets at once). I like his separation of the solar panel and charger. Lets the user quickly swap out a panel, plus you could charge the batteries from any (appropriately regulated) power source when there is no sun.
BTW - he got recently his first batch of chargers funded via KickStarter!
Bootstrap solar is awesome and yes the bamboo case appeals to the tree hugger in me (and I’m a capitalist). I really like the idea of two solar panels as one of my Gadgeteer experiments actually requires multiple smaller panels as compared to a single large panel, so this might be pretty much what I was looking for and with a nice case to boot. I’ll have to see how long it would take to get it to me if I order it.
Kickstart sounds and looks interesting, and I would think that you have some ideas/products that you should consider putting up there or somewhere else to develop them commercially (nothing wrong from making a living developing your ideas). In many ways I understand Ryo and I suspect we share at least a somewhat similar history and are working towards a somewhat similar future (except I’m much older).
As a side note sometimes in a disaster you might have a working cell phone, but the problem is the local cell towers have been knocked out as I’ve seen that before. Sometimes there just isn’t a replacement for HAM radios.
I’m very excited about Gadgeteer as I think electronic devices have been a neglected area for far too long and Gadgeteer I hope puts some excitement and interest back into the concept of electronic inventors. I hope that GHI Electronics building their own assembly facilities (in Detroit no less) is an indicator that people are really getting into this and I suspect it is.
@ Duke - The adafruit solar LiPo chargers are in stock. If you’re going to get one, do it now. Last time I waited two days and they were gone. It took 2-3 months to get them back in stock.
I bought the Chi-qoo from BootstrapSolar (extra solar panel, AC plug, etc), as it looked pretty good and appealed to my inner tree hugger. Now the trick will be to see if I can keep it away from my wife as her inner tree hugger will no doubt think its cool as well.
Thanks
That’s why it has 2 USB ports… so you can share 
Thank you people for sharing your experience and calculations. You have done a great job! Solar panels definitely bring great changes to every house, especially when you charge a car with their help. Though, my approach was a little bit different, because before usage of my PV panels for such purpose I consulted my http://solarpanelscompany.com/. Apparently, equipment differs and it can be risky to do something without proper instructions. At the same time, I am proud of people, who try to find the answers themselves.