For $175 (or $265 with all the options) you can keep all your gadgets charged. If you're comfortable thinking in volts, amps, and watts it's pretty easy to design your own system.
The Core System
$20 Renology 10A solar charge controller
$55 50 Watt 12V Solar panel (many commodity options)
$70 12350 12V 35AH battery (many commodity options)
$30 excessively heavy M4 power cables
total: $175
Charge controller
The key piece is the charge controller. You can read its manual and it will tell you how to connect all the other pieces. I got a 10 Amp controller, small, cheap, a couple frills, and I am totally happy with the Renology unit I got. Other units look fine too.
Solar Panel
Since this is a solar system let's talk solar panels. If you're looking at the specs of panels a "12V" panel will have an "open-circuit voltage" and "optimum operating voltage" higher than 12 volts (my 12V panel rated those as 23.3V and 19.8V). That's fine, the charge controller knows and will manage this. By having a higher voltage at peak it can deliver 12 volts more of the time at times other than noon or if there's a little cloud or tree shading your panel. My 50 Watt panel claims 2.6 Amps of "short circuit current" and that 2.6 Amps is well below the 10 Amps the charge controller can handle. So far so good. You could choose to go bigger or smaller here, down to a 10 Watt panel or up to a 200 Watt panel.
Battery
I got a good deal on a used 12350 battery but they're about $70 new. They're a pretty established common item and lots of makers will make them just as good. You can also choose to go bigger or smaller on your battery. Depending on what you're planning to run with this system it might be important to get a bigger battery because 12V lead acid batteries are most efficient used slowly. The 35 Amp-Hour rating is true if you use it at 1.75 Amps over 20 hours. 1.75 Amps * 12 Volts is 21 Watts. You can drain the battery faster, but it won't deliver it's rated capacity. If you plan on running 50, 100 or more watts worth of devices you should probably get a bigger battery.
Cables
Solar panels now commonly come with "M4" connectors which are waterproof and pretty simple to hook up. You can buy connectors and cable and put them together, or just buy assembled cables. The cables it was easiest for me to find were scaled for a full house system of 1000 Watts or more, and I'm only doing 50W. Maybe with a little searching you could find something cheaper but good enough.
Powering Your Stuff
Now that you have the power, you want to use it. The charge controller I got has two 5V 2A USB-A sockets built in which is handy, but there's lots more. This is a 12V system, and there's a world of 12V accessories out there. For $5-10 you can get a 12V accessory socket, wire that to your battery directly or the output on the charge controller, and start plugging things into that socket. NiteCore makes battery charger that run off 12V that I charge my rechargeable AA batteries with. EBL makes a AA/AAA charger that runs off USB which is quite handy. For powering my laptop I found a $20 adapter from Philips that plugs into a 12v socket and delivers 60W of USB-PD. My MacBook is plugged in and charging as I write this.
An inverter is the big hammer of making it Just Work. An inverter takes 12V in from the battery and produces 110AC like any wall outlet in your house, almost. Cheap inverters ($20-50) are "modified sine wave" and will do okay at powering things but may be inefficient and won't work with some picky devices. Better inverters are "true sine wave" or "pure sine wave" ($70 and up) and should be more efficient and produce power most like what you get out of any house outlet. Any inverter will have a wattage limit. A typical house outlet is limited to 1500 watts. A hair dryer or kitchen appliance might use that full power, most things will be smaller. Do your research on the devices you care about, and maybe get a kill-a-watt and measure how much power a device actually uses.
Remember that the battery limits your wattage too. If you're using 12V lead-acid batteries you should optimally have 170 Amp-Hours of battery for each 100 watts of power you want to pull from them. I've been pulling 60W out of a 35AH battery and it works for a little while but it's not great. My next system will be bigger and better!
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