Testing a foldable solar panel today.

[Captain Kirk!]

Keep in mind if it is SHTF you will have no need to charge cellphones.

We had a three day power failure out here from Ian and cell service went out because their genset ran out of diesel.

Likewise landline communications which is required to backhaul cell sites will also go down.

Cellphones will become useless.

So gps, cameras, recorders, etc will be worthless?

[Call_me_Ishmael]

Update.

Around Thanksgiving, I paralleled two foldable arrays. They both feed into one charge controller and double the power. Very very pleased with the result. I gave the whole set to my daughter, along with a tester and spare parts. She was excited (NOT).

For applications requiring only a few hundred watt-hours per day, these foldable panels are great.

[Wilson2]

I want to give a portable 60 watt panel my daughter to keep her Garmin InReach powered in the event of SHTF. It has a built in USB port and I know it easily provides USB at 2 amps. I've tested that. But that's only 10 watts. I am going to connect it to a cheap MPPT controller and see how much I can get for charging some LiFePO4 batteries. I'll report later

People overthink these.

We have a bunch of homemade small solar systems around the farm.

Charge controller - most are 10A 12V/24V PWM waterproof, I think 2 are 20A. All are smart and monitor the battery for type and charge level and charge appropriately. Good ones are $20-$40. Easy to get on Amazon.

Battery - deep cycle, 12V about 18 Ah (some larger), usually we just go to Walmart and buy them. $25-$65 depending on size. We get the NB terminals because you can turn those in for the core charge discount and the battery gets recycled. These last 4-8 years usually, depends on the usage (one lasted 12 years). We get these smaller batteries because they work and are not that heavy, makes the total assembled system portable.

Solar Panel - you have to match this to the charge controller. A 120 W 12V panel is about $100, roughly 3x2 ft. Some of ours have 180W panels.

Container - we get something like the heavy duty storage tote from Walmart, Lowes, etc. about 10-12 gallon size with a lid that has latches. Maybe $10-15. The 10 gal holds the charge controller and 18Ah battery, fuse, switches, (and inverter if you add one). Drill a hole in the side to pass wires, get a grommet/edge protector to seal it. Put weatherproof on/off switches, USB ports, DC outlet & AC outlet if needed, on the side.

Thats all for DC, for AC you need an inverter. For the systems that need AC we get ones that are true sine wave so they are a little more expensive. Anywhere from $50-$200.
For the DC system with wiring and fuses total is about $200.

We have these in the greenhouses to operate the lights and water timer. The tote box is in the greenhouse, the panel is outside. The greenhouses have misters so the solar systems get watered every day. Never had any problems.

We have one that just sits out in the open, no protection from the elements at all. No problems.

[Captain Kirk!]

Let me also add no shtf electronics are worth a shit unless you store them and transport them in a faraday cage/bag.

^^ This.