This Instructable is on how to build a battery power pack that charges from the sun. I built it this past summer to have a portable device that I could run and charge my  gadgets on.

Step 1: Wiring Diagram

The first thing I did was draw a wiring diagram.

Where did you buy your inverter?
I bought it at meijer for $21.99.There are also many other places you can get them from. If you don't have a meijer near your house, you could get one from a hardware store or from Northerntools.com<br />
ok, thank you. I am planing on building 1 for myself<br />
Cool; post pictures when you are done.<br />
ok<br />
Yeah, good work!&nbsp;<br /> I&nbsp;plan to make my own - but with&nbsp;a bit modification:<br /> I&nbsp;won't have your bridge rectifier - just a diode (still don't know how I choose which type)<br /> Is your SPST&nbsp;switch for the solar panel charging the battery?&nbsp;Why?<br /> I was going to have the solar panel always connected to the battery - with a trickle charge indicator that will shut off current into the battery.<br /> Then, for outputs I'm going to also add a USB&nbsp;port along with standard wall plug.<br /> <br /> Have fun with your project, it's the best damn idea people don't have yet!
<p>Yes, the SPST is for the solar panel charging the battery. The reason why is because I didn't install a charge controller that prevents overcharging and so I put a switch to control charging manually. Also mine does have a 2 standard wall plugs and a USB port; that is what the inverter is for.</p>
<p>Why is the bridge rectifier needed, as I thought the solar panel's output is DC?</p>
It's not actually needed. I was confused on the purpose of a bridge rectifier vs a diode which should have been used. In fact, the panel I used has a built in diode so wouldn't have needed to install one at all
I'm just learning electrical systems and engineering - If I&nbsp;wanted to bypass the rectifier (I don't have any plans with wind turbines!) what type of diode would I use &amp; rating, and how would that change this layout?<br /> <br /> I've been planning on making this for a long time and I&nbsp;thank you for your effort on this DIY!
If you use the solar panel I use, you won't actually need to&nbsp;install&nbsp;a diode because the solar panel has one built in.
Can you send me a proper diagram or advise to build a system for my power chair. Im a vet and like to spend time outdoors but cant in most cases because of rechargeable sources. My chair has 2 gell cell batteries with a regular charger. Wonder if I could go direct panel to my batteries. <br><br>Please, please advise. Thanks
<p>How many AmpHours is the battery? I have a 17Ah, what output could i get from this?<br>Great instructo!</p>
Mine is rated 75 amp/hr (I tell about it in detail in step 2)<br><br>A 12 volt 17Ah battery would equal out to about 200 watt hours. That means, for example, you could run something with a 50 watt draw for 4 hours
<p>I would really like to build one of these for myself. Could you use a automotive style voltage regulator to keep from over charging your battery? Or is that completely different from something you would use with a solar panel? Any info is appreciated Thanks</p>
<p>I'm not sure what type of regulator you are referring to. With a panel as small as I used, you wouldn't have to worry about over charging the battery. Many larger solar panel set ups come with a charge controller, or you can buy one for a reasonable price online; just search &quot;solar charge controller&quot;</p>
have you thought about using two batteries and a charger controller with a 15 watt solar cell then yo could in stall a larger inverter and use it as a full generator for work applications and possibly even build them to sell and make a business I use similar setups for long camping trips wish I would have thought about a rolling tool box though
Thanks for the suggestion. Since I made this instructable I have made a couple more and sold. The one had a larger 101 Amp/hr battery with a 15 Watt panel. The last one I built had a 101 amp/hr battery, three 15 watt solar panels, and a 900 Watt inverter
I'm curious about whether this will function as both powering something (like the stereo in the picture) while still charging from the solar panel, all at the same time. Or is it a choice of one or the other?
You can plug into the panels to charge and power a stereo or whatever else you want at the same time
That's awesome, thanks for everything!
Commercial Solar Panels are Expensive!<br> Fact: It will take you more than 10 years to pay back<br> Solution: Using Surplus Solar Cells You can get pay back in 1-2 years<br> There is an Engineer from Chicago his name is John Sommer<br> He explain it All in his diy solar panels Blog&nbsp;<a href="http://topdiysolarpanels.com/" rel="nofollow">http://topdiysolarpanels.com/</a>
Dave, great project. Can you provide more information on the bridge rectifier? Brand / Nomenclature? Where did you install it in your toolbox? Thanks.
I think it would be a good idea to also add some ventilation to this just to help with efficiency in a situation where you would want the lid down. it looks like you have the lid closed with the Solar panel on top for support. If there are no vent ports, the inverter will heat up. Without a charge controller this could be even more important for your battery. Your solar array probably isn't large enough to cause a major problem, but on a small scale, heat reduces your efficiency.
If I have 2 40watt 20volt solar panels that is connected to two CSB gp12650 12V 65Ah batteries, how much watt of inverter do I need? If I fully charged the batteries (includes the solar is still running) and connect to a window unit air condition that sucks up 900 watt, how long will the A/C last?
2 X 40 Watts = 80 Watts<br> 12 hrs. of sunlight everyday X 80 Watts = 960 Watts<br> <br> Every day you could use the air conditioning for only 1 hour. If you are running the air conditioner on the inverter you would need an inverter that was at least 900 Watts. In my opinion if you want some kind of air conditioning I would suggest making one of these-<a href="http://www.instructables.com/id/Portable-12V-Air-Conditioner---Cheap-and-easy!/">http://www.instructables.com/id/Portable-12V-Air-Conditioner---Cheap-and-easy!/</a>&nbsp;-This one even runs on 12 volt so you wouldn't even need an inverter.
What is the Wattage on your solar panel?
The one shown is a 5 Watt panel, but since then I have bought a 15 Watt panel which is what I now use.
Instead of using a big inventer! can you use a small in-car inventer.<br>
Yes, actually that is what I originally planned to use but I found the 400 Watt inverter on sale so I decided to use it instead.
can i use a 1000 watt inventer instead of 400 watt one?<br>
where did you get the solar panel and what voltage and amperage is it?
I bought mine at Tractor Supply Co.( <a href="http://www.tractorsupply.com">http://www.tractorsupply.com</a>) But since then I have found them for cheaper at menards and Northern Tools (<a href="http://www.northerntool.com">http://www.northerntool.com</a>) The one shown is&nbsp;~15 Volt&nbsp;and only 1/3 Amp,&nbsp;but I now usually use a 15volt 1 Amp panel.
This generator is a big help to some home owners. This is a plus factor that can<br>save energy as well as money. Solar energy is an advantage to those who wants<br>to save energy and won't spend much money.<br><br>Great post. Keep sharing.
were did u buy the tool box for 22.50 at. what store
I bought it at walmart
thanks alot for info
&nbsp;So this 12v plug is just running straight of the solar panel and not the battery correct?
This is the power output&nbsp;plug to plug in things such as a cell phone car charger. The plug in step 5 is the input plug for the solar panel. Both the output and input&nbsp;plugs&nbsp;are connected&nbsp;to the battery.
&nbsp;oo ok, doesn't your diagram show an output car 12v plug? &nbsp;I thought that was what this was
Yes, this one is the output plug.
&nbsp;What size of a panel and an inverter would you need to run a hot plate and an small electric room size heater? Does anyone know and would be able to help me? Can I do that? Thanks, Patricia
<p>Patricia,</p> <p>As Spanbox and isacco have said this setup is too small for running heaters and hotplates.</p> <p>What I would suggest for a heater (if you're wanting something portable) is that you should get a small propane heater such as this one. <br /> <a href="http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200362083_200362083" rel="nofollow">http://www.northerntool.com/webapp/wcs/stores/servlet/product_6970_200362083_200362083</a></p>
A solar system would be very expensive to do what you want. Generating heat from electricity requires <strong>a lot</strong> of electricity. Solar systems, batteries and inverters are never 100% efficient either, so, to use a 1000W heater or hotplate for 1 hour you would&nbsp; need about 1200W/h of stored energy.<br /> At 12V, 1200W will draw 100amps. So, if you have a fully charged 100A/h battery it would be dead after 1 hour, but draining any battery is bad for the battery.<br /> Better would be to have 5 x 100A/h so that each one only uses 20% after 1 hour, and stays 80% charged. A 100A/h deep cyle leisure/solar battery does not come cheap, let alone 5 of them. Then you need an expensive inverter capable of the high load, and then enough solar panels to charge the batteries again.<br /> <br /> I would think about trying to use a different method for generating heat e.g. a gas fire or a gas hotplate. Wood is also carbon neutral and a good source of renewable energy.<br /> <br /> Hope this helps.<br />
Usually, a hot plate or an electric heater has between 500 and 1000 watts of power consumption. A Silicium mono-chrystal panel delivers a nominal (maximum) power of about 100W per square meter. The battery and inverter should be sized on this power. It would not be a portable system.<br /> <br /> Isacco<br />
&nbsp;I could purchase enough panels and an inverter I saw from Coleman was rated at 100o W. But, I don't know what I would need in batteries. Can you help? Thanks
I know some basic info because I am exploring the market for a photovoltaic systems for my house. <br /> From my market investigation (I am in Italy) the cost of 1 Kw nominal power (panels + inverter) is between 4000 and 5000 Euros. <br /> I cannot give you more technical details because I am not an expert. May be you can post your questions in forums devoted to photovoltaic energy.<br /> Isacco<br />
&nbsp;Great idea for camping or emergencies (or when you want to be cool and tote it around with you for max battery life)<br /> <br /> but a lot of the build pictures didn't give a relative view of where you put everything inside. I know the battery was in the bottom and braced with wood - but besides that I have no idea of where anything else was at.<br /> <br /> Would you go back and take some zoomed out shots of everything to help me understand placement so I can build one myself (maybe even a better one)<br /> <br /> also some more info on why you did what you did - what was the reasoning for using the 12v plug instead of a standard wall plug for power from the solar panel to the battery. just touch up and such like that would be appreciated.<br /> <br /> Awesome build!<br />

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Bio: "CAN'T can't do anything until TRY comes along and does it" -Grandpa
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