Any good outdoor weatherproof solar power packs available yet?

Not to get to much off on a tangent, but when I dealt with some solar powered systems for remote weather stations, I ordered the Concord Sun Xtender AGM (Absorbed Glass Mat) and really liked their performance as well as not worrying about tipping/acid problems.
 
Of course, they are more expensive... ;)
 
I have used this solar panel on my game feeders.   It is connected directly to a 1280 sealed lead acid battery.      It is relatively bulletproof with a flexible steel casing over the wires to eliminate varmints chewing on the wires.   I have not done the calcs to see if this would meet your electrical needs, but it works well on the feeders.   
 
I've done a little more research, and it seems to be indicating that the only solution for a long-term installation requires the solar electricity producing elements to be mounted directly behind clear *glass* and hermetically sealed against moisture.  Allegedly, anything other than glass, whether it be polycarbonate or epoxy or whatever, will yellow with time (some materials faster than others), eventually choking off (or at least greatly reducing) the useable sunlight.  Is it true?  If so, it seems like relatively few tiny solar panels are built to last very long.  I mean, I haven't seen *anything* solar at the consumer level (whether it be simple solar garden lights or whatever) that uses glass.  It does seem like consumer grade stuff yellows over and loses functionality, generally in about a year or less, and maybe the lack of glass at least partially explains why it so quickly disappoints and becomes trash.  It really is odd that there don't seem to be many (any?)  consumer products which differentiate themselves by at least attempting to last longer than the lowest common denominator.
 
Anyhow, I'm prepared to switch to a low power design to hopefully reduce the solar energy costs to a much lower amount than what was costed-out earlier in this thread, with the hoped-for payoff being no future battery changes.  So far, the smallest/cheapest solar panels I've found that use glass are from China on ebay at around $10 plus a 6 week delivery wait, but even then it's a roll of the dice as to how well they're moisture sealed, etc.:  http://www.ebay.com/itm/1-3W-5V-260mA-Tempered-Glass-Mini-Solar-Panel-Module-System-Charger-DIY-CA-/251586862369?pt=LH_DefaultDomain_2&hash=item3a93bedd21  No claims are made about moisture sealing, and it's not even mentioned.  Is there a better source?  With current low power options, it's possible to build sensors that consume an average of 100microamps or less (some as low as 100 nanoamps or less with extra special effort tweaking the sleep states and waking up only infrequently and very briefly).  For instance, you can strip the arduino down to the barest of bones (basically just an ATMEGA328P and a few resistors and capacitors) and achieve it that way.  I'm shortly about to do just that (as described here: http://gammon.com.au/power).  It seems we are at the beginning or middle a major trend right now toward ultra low power consumption devices which are to be powered by "energy harvesting," such as solar.
 
Yeah, I think any kind of plastic is going to yellow or fog over with time.  You can see what the result will be by looking at all the foggy headlights on older cars that suffer from this problem.   And you're right, if it isn't hermetically sealed, moisture WILL get in there.
 
I really don't understand what you mean, the solar panel itself?  Are you using 'indoor' rated ones and trying to 'protect' it from the outdoor environment with glass?
 
What are your voltage and current (or wattage) requirements over a 24 hr period?
 
You can get outdoor rated solar panels that have a ten year warranty that are made for the outdoor environment (links below).  Yes, they are double the price of the ones you posted on Ebay, but then... ;)
 
http://www.solar-electric.com/solar-panels-mounts-kits-accessories/solarpanels/1to39wasopa/poup25wa12vo-html.html
 
http://www.solar-electric.com/solar-panels-mounts-kits-accessories/solarpanels/1to39wasopa.html
 
As far as a battery, you will have to splurge a bit, but the one I linked to above had very good performance for me in 110 degree summers.
 
If you want, call Northern Arizona Wind and Sun and speak with an applications person about your situation.  When I did this, their application person had a basic understanding of solar charging and battery life/usage (though this was several years ago).
 
BraveSirRobbin said:
I really don't understand what you mean, the solar panel itself?  Are you using 'indoor' rated ones and trying to 'protect' it from the outdoor environment with glass?
 
What are your voltage and current (or wattage) requirements over a 24 hr period?
 
You can get outdoor rated solar panels that have a ten year warranty that are made for the outdoor environment (links below).  Yes, they are double the price of the ones you posted on Ebay, but then... ;)
 
http://www.solar-electric.com/solar-panels-mounts-kits-accessories/solarpanels/1to39wasopa/poup25wa12vo-html.html
 
http://www.solar-electric.com/solar-panels-mounts-kits-accessories/solarpanels/1to39wasopa.html
 
As far as a battery, you will have to splurge a bit, but the one I linked to above had very good performance for me in 110 degree summers.
 
If you want, call Northern Arizona Wind and Sun and speak with an applications person about your situation.  When I did this, their application person had a basic understanding of solar charging and battery life/usage (though this was several years ago).
Click to expand...
 
Yes, just the solar panel itself.  I'd rather not adapt anyting.  I'd rather it already be good-to-go for outdoor use.
 
Assuming this guy's moteino measurements (https://www.youtube.com/watch?v=jVHbWjcpeM8) using a Fluke 87V are valid and a reasonable proxy, then let's say the the power requirements would average 300 microamps at 3.3volts.  That's for the case where it does a wireless transmit every second.  As he demonstrates, that could be scaled back quite a bit just by transmitting less often (e.g. averaging 70 microamps if transmitting once every 8 seconds).
 
BraveSirRobbin said:
...and did you see my links?
Click to expand...
 
Yes, they look like very nice panels.  Thank you for the links.  However, aren't they overkill for a drain current that averages 300 microamps at 3.3 volts?  Or perhaps they're just what I need to cover a worst case mounting scenario.  I have no idea how well or how poorly panels perform when not pointed directly at the sun and perpendicular to it.  Maybe it's best to assume they only pickup ambient light rather than assume they're installed under ideal conditions....  
 
I don't know how a $25 part could ever be considered overkill - if you spend 10 minutes thinking about how to adapt something else to work and last for $10 - that's $15 difference (minus whatever adaptation you might need) - if you were making a million of these, sure that makes sense - but as a DIYer making one or two, it's hard to imagine it's worth the effort.  Heck, just the time BraveSirRobbin spent finding that link is worth more than $15.
 
Actually, at 3.3 volts the panels I linked to would have to have a regulator on them (could probably find one with a smaller current rating and not as costly).  I think he found a 3.3 volt solar panel, but it was for indoor use that was small enough for his liking (mounting scenarios).
 
I'm not sure if you will be able to find a true outdoor rated solar panel at that low of a voltage.
 
Ah OK - I'll keep my mouth shut then...
 
I actually am curious of the outcome of this as I kinda wanted to do something similar that I could make about 25 of to do sensing and transmit updates frequently, all self contained and solar.  I was even considering buying a pack of cheap solar lights to butcher and use the solar panel and charger piece and battery pack as the starting piece...  But - I have zero time to focus on that right now so I'll watch from afar.
 
Just FYI.  I did a bit more searching, and the trendline is starting to look as though the power requirements for IoT devices is falling at such a rapid rate that energy harvesting is paradoxically becoming not only more feasible but also less important.  I just ordered a couple of inexpensive IoT radios (based on a TI chip) that claim to have a "deep sleep" power requirement of just 200 nanoamps.  That's already practically nothing, and that's today.  Future chips/components/devices will probably deep sleep at even lower currents and eventually at lower voltages too.  So, the tradeoff is starting to look like: do I easily attach a battery that lasts many years, or do I deal with the hassles and relatively higher expense of energy harvesting?  TI has an energy harvesting "booster pack" for their mcu stuff that they introduced in 2009 for $150.  The price today?  Still $150, and they don't seem to have added any new energy harvesting stuff over the last 5 years.  However, they have kept aggressively hacking away at the power requirements of their gear.  
 
Anyhow, just a theory, but maybe this explains why the smaller scale solar options for IoT stuff has remained stuck where it is.  That's just my hasty reading of the tea leaves, and maybe somebody else has a better analysis with a different conclusion.   Meanwhile, when time permits, I'll start looking for batteries with extremely low self discharge and high longevity over a wide temperature range, as I'm guessing that's where persistent wireless sensor networks are heading.  If anyone already knows where the sweet spot for that is, please post.
 
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