Was at Hawaii Kai Costco yesterday and noticed the Goal0 guy was back with a big stack of gadgets on a table. Checked the prices back at home and it's a significant savings over what you would pay online. I picked up the Guide10 Adventure kit with the 7watt panel, AA Charger, and Rockout mp3 speaker. It didn't come with the AAA adapter but I might just fabricate one on my own. Just the panels by themselves are $20 what you would pay online, and if it doesn't work out then who cares. It's Costco. Take 'em back.

Just a heads up the guy is going to be there until Jan 6.

That's the same one I got. Starting to build up my collection and they got some great products.

FWIW, I think you can get it cheaper with DIY components.  My GF bought one despite telling her I got a same size panel (10w) for $60 on Amazon with a regulator.  If you are knowledgeable with electronics you can put it together for less.

Hey ren, do you have a list of the components you used? I was thinking of putting together a small kit and figured it could be cheaper to piece together.

bought my panel here: http://www.amazon.com/exec/obidos/ASIN/B004FWW1M4/?tag=2ahawaii-20
For 5V DC out put from a 12V source you can look for used mobile phone chargers (in car) and take them apart, find the 5V out and solder a USB female connector on it for USB charging.  Of course know the pin layout of the USB connector first
or you can do this with a 7805 5V reg. http://blog.makezine.com/archive/2009/02/simple-standalone-5volt-regulator.html  be aware that it is only capable of supplying 5V at 1A. You can buy it at your local RS http://www.radioshack.com/product/index.jsp?productId=2062599
You will need a battery to store.  I found that 12v car type batts are too big for that particular panel.  A small 3ah sealed lead acid batt found in back up power supplies should be OK to handle small chores and storing the electricity from the small panel.  The panel while it will produce about 22V in direct sunlight doesn't have the current to charge a large battery. 
If there are electrical engineers on this board I'd like to hear your ideas and thoughts
As you can see the only thing I bought was the panel and the rest I found lying around the house or friends that give up stuff with parts in them.  i.e. there are lots of mobile phone chargers out there and backup PS with some useful life batteries.

Glass matt motorcycle batteries are handy, too. Discovered that by accident the first time I replaced the battery in my bike. Looked at it, saw that it was a deep cycle glass matt battery and thought "Hmmm, might not have enough juice to start the bike reliably but I wonder..."

Hooked it up to a few DIY solar panels I've cobbled together and it worked great.

Goal specific little systems are fairly easy to put together from parts but its a hassle to regulate voltage for each task. A simple 12v system, like the Goal Zero stuff, is easier to plug things into and the charge controllers are dirt cheap. I've run my computer off the little system I made using a 12v power cord (to avoid a DC/AC conversion and the crappy power it produces), 4 panels the size of notebook paper (but 1/4" thick), the charge controller and the 12AH motorcycle battery.  For more portable (i.e. light weight) systems I've use a little 7AH battery from radio shack just to regulate voltage. Doesn't store much but keeps the operating voltage of the system in the right place.

The tough part is easy portability and robustness. The Goal Zero stuff is built to haul around, uses standard cables, etc. And I LOVE that the smallest system uses AA's as its power storage. Talk about easy to replace! You can buy AA rechargables in bulk for about $1 each and store power for your small electronics like there is no tomorrow. And light. If you build an electronics scheme based on AA's then this is a very easy way to keep them going.

I've done exactly that with AA based audio for video gear while on remote locations. A hassle but far less a hassle than any other solution except bringing 200 batteries with you. By getting a AA charger with a USB output (handy!) I was able to use the AA's as a battery bank for small electronics just like the Goal Zero systems. 12v charging, though, instead of a more portable self contained 6v system.

I also have an Android Tablet that sips power. Perfect for solar power though not as useful as a full PC. I managed to run the thing off solar power for the first 6 months I had it. Could have gone longer I just had to disassemble the system for painting the house and never bothered to set it back up again.

Links of potential interest....
Crap. The site I was going to link to is down while the company is on vacation for a couple weeks. Oh, well. I'll post the links to some decent cheap stuff when they're back up.

hey heavy, if you dont mind my asking but what did you pay for the goal zero setup ?

Aloha

I went to a trade show back in October here in Hawaii and there was a company showcasing milspec foldable PV arrays.  One of them even had a  9mm bulllet put through it to demonstrate minimal degradation in power output from the array.  I will try and find the handout I grabbed from their booth and post their link.  The only thing with them is their sutff was super expensive.  The show price was like $650 for a three panel array.  The cool thing about it though was that you could hook the panel straight to any cel phone or other electronic car charger type of thing.  I'm an electrician by trade and have been monitoring this whole solar movement since the 90's.  The stuff they got out there now is hundreds of times better then what first came out.  What I want to do is go with four motorcycle batteries (2 in series and then put the two pairs in parallel) and use 12v (automotive kine) LED's.  There are a lot of SMD LED strips that have small draw and cast choke light.  A lot of the strips out there can be joined together too.  This would be my primary lighting.  I would also just use a USB car charger to charge my small electronics (phone and Droid tablet).  The generator would be for the fridge only and all cooking would be done over a fire or a on a gas stove.

Hi kala and all,

Is the panel at Costco better than say the Voltaic Systems 10W panel? 

http://www.voltaicsystems.com/fuse10w.shtml

The Voltaic's kind of expensive but I am contemplating getting this one as it charges laptops too.  What do you think?

The company I saw at the trade show is called Green Path Technologies.  Here's a link to their website and a link to an article from Pacific Business News about them too.

http://www.bizjournals.com/pacific/print-edition/2011/10/07/greenpath-technologies-takes-solar.html

http://greenpath-tech.com/

And this is a picture of their large foldable panels that the military purchases from them.  The one I was looking at a was a small one with only two arrays.

Lol small world. I actually know those guys as a customer of mine uses them for their solar panels.

The Voltaic's kind of expensive but I am contemplating getting this one as it charges laptops too.  What do you think?

It is expensive. Part of what you're paying for is that battery - which is really cool. Nothing beats lithium batts for weight. It won't last long, though. 3 years is about max useful life from them whether you use them much or not. They also die if you don't use them. The self discharge over time and if they ever hit bottom they never quite come back up to full charge. Damned if you do, damned if you don't so to speak. They are common in laptops because the manufacturers figure you'll buy a new machine by that time.

The issue I have with such systems is that while they are convenient they are very temporary. All the charging electronics are in the battery pack so 3 years from now (or much sooner if you use it a lot in a hot environment - which under the solar panel tends to be) you have to replace the battery cells or the whole device.  Keep that in mind if you're looking for a solar setup for long term power.

As for charging a laptop - that battery will run a normal laptop (i.e. not a netbook) at full tilt for an hour or 2 max. A 60 watt hour battery can provide up to 60 watts for an hour and most lappy power supplies are rated to 50 or 60 watts. That's running at full speed and charging the battery at the same time, though. Best use of the solar batt is to either charge up the laptop when it is off and/or use it when the laptop battery is fully charged.

Its a lot of money for what usually ends up being a dissapointingly small amount of runtime for a laptop. As long as you understand and work with the limitations, though, its a great way to get power on the fly.

Nothing beats lead acid batteries for long term reliability vs. cost but they are a bitch to haul around. If you're looking for longer term emergency power (this is the preparedness forum, after all) the slick little lithium poly batteries are not a great choice. 

The flat goal zero battery is significantly better: Lithium Iron Phosphate. MUCH longer life battery due to less degredation. Their medium system is $400 and worth every penny more than the Voltaic simply because of the battery. NOT the round battery with the handle - that's lead acid. The Sherpa 50 is the good one at this price range. At $200 for that battery... I may have to buy one.

Thanks clshade for the excellent analysis!  I will check out the one at Costco or maybe look at a DIY project.

I found an instructable for a similar design: http://www.instructables.com/id/SPREE-Solar-Photovoltaic-Renewable-Electron-/

^^^^^^

Good catch!

5 watts is a bit anemic but would work for small electronics and not take forever to recharge the battery. You could also buy 2 or 3 and hook them up in parallel for 10 or 15 watts.

Not sure about that model of panel, but one thing missing from description is a diode that keeps the battery from discharging through the panels at night. Some panels come with them which is less efficient when stringing those panels together but it still works fine. Could be that its built in to the charge controller, too. Lots of charge controllers don't so you have the option of using the right diode for the power of your panels.

Either way - something to make sure of when buying stuff for a cool DIY project like that.

How do you figure out how many amps and watts and stuff you need? Is there a formula and stuff? And does it work for all appliances in my household.

hey heavy, if you dont mind my asking but what did you pay for the goal zero setup ?

Aloha

It was $125 for the panel, AA charger, and mp3 speakers. Could live without the speakers but figured i'm getting them for free so might as well use them on the job site.

Mostly interested in putting together items that use AA and AAA for lighting when the power goes out. Charges the Gopro as well so that's a bonus. I'm going to put together a larger system with an inverter that can run basic power tools, but it's nice to have something small that will ride in a backpack. Also got the usb Luna LED light which I know will come in handy for camping. May go pick up a couple tomorrow since they are only $7

That is a deep, dark rabbit hole Mr. Monkey.

Take the blue pill and stay in Neverland.... or take the red pill and see how deep the rabbit hole goes... 

The short answer is that, yes, there are formulas and they do apply to the home and appliances. They are scary. Not because they are complex but because they usually mean you have to spend a lot of money to feed your energy habit via solar power. There are many reasons for this:

1) Our appliances are made so suck power with abandon because they are easy to make that way and our power is fairly cheap
2) Solar panels are expensive
3) Storing adequate power for when the sun is not shining is an additional huge expense.

But, to the point....

Watts = Amps X Volts.

We'll assume a 12 volt solar set up for simplicity's sake.

Say you have a 10 Amp Hour (AH) 12 volt battery. This is tiny and just used for example.  Also for tiny example, let's way we have a "10 Watt" solar panel. (Enter the rabbit hole...) Now that doesn't mean you'll get 10 watts out of it. It is usually an 18v panel but the battery is going to pull that down to around 12v in actual use. So an 18v panel giving 10 watts is...

10 = 18 X ~.5555555

That is a .5 amp panel rounded down for lots of reasons. Its still probably a little high.

So... filling a 10AH battery with that 10 watt panel will take... 20 hours of max output conditions. In Hawaii that's from 10am to 3pm if you move the panel to catch the sun directly.... etc. In real life its more like 3 or 4 days of brilliant sun for that tiny panel to fill that tiny battery.

That 10AH battery would power a single 40 watt florescent bulb for.... back to our formula...

40 Watts = 12 volts X 3.333 amps. (Yes, I know. This assumes a 12v bulb and leaves out the 10% or so inefficiency of a DC/AC conversion)

3 hours. 10AH divided by 3.33 amp draw.

But (deeper we go...) If you draw a battery at more than 10% of its rate it is far less efficient. That will likely be more around 1.5 hours.

The solution is to get a MUCH bigger battery. If you want to run that light as efficiently as possible then you'll want a battery that is 10 times it's amp draw - we'll say a 35AH battery.

A 35 AH battery would take a week and a half to charge with that tiny panel and run the 40W light for.... 10 hours.

So... we need a larger panel. Say we use that light only for 3 hours a day. That's 10AH. So we need enough panel output to gather 10AH of power during the good light from 10 to 3 - a 5 hour window. Voila - we need 2 amps of panel (~30 watts, rounded up for safety) to:

1) Gather enough power to run that bulb for 3 hours a day
2) With a battery large enough to handle the load efficiently.

So that's a $70 battery and a $130 panel to run a single 40W light  bulb for 3 hours a day. Add a charge controller for $25 and some other bits for an additional $50 or so.

The nice thing about that example is that you can probably run a laptop off that for about the same amount of time - if you don't use the light. For systems up to 500W or so you won't have to upgrade the charge controller, either.

As for appliances, a 500W system would probably ~run~ your fridge without any trouble but it will choke on compressor when it tries to kick in. The answer, of course, is yet more battery which would then seem to demand yet more solar panel, larger inverter, larger and more complex charge controller...

You see how this goes? Its actually cheaper in the long run to drop $1200 on a 40 watt solar fridge. Yes, a full size fridge/freezer that runs on 40 watts - same as the light bulb. Worth its price if you are trying to live off the grid.

That's the basic process, though. Small systems are relatively cheap, easy to set up and rewarding. Trying to seriously reduce your dependence on the grid requires either serious cash or a serious commitment to changing your energy habits, appliances and less (but still serious) cash.

A good resource for more information are folks who live in RV's. A lot of them use solar to help avoid having to run the engine to beef up the batteries. Here's a site that I found really helpful when I was digging through all this stuff a few years back: http://www.marxrv.com/12volt/12volt.htm

I chose to go the route of a small system - mostly cobbled together from cheap junk on ebay - that I can use to charge my laptop, tablet and AA batteries in addition to a couple marine batteries from WallyWorld. Then I favor devices that run on AA's or charge via USB. That gives me enough power for emergencies since I keep the marine batts topped off and small scale stuff to play around with - charging the cell phone and other gadgets. Fun, a good exercise - but nowhere near cost effective unless you value the self sufficiency enough to offset the costs.

Which is the niche that Goal Zero is filling pretty darned well.

thanks for that informative writeup clshade.