In that case, it will depend on how many days you need it. Something like the Goal Zero Yeti Lithium 200X Portable Power Station can charge most laptops about 4 times, so if you are only out for 4 days before going someplace to recharge the power station, it would save you from having to get a solar panel entirely.

I'd ask yourself how many days you need power between town trips, and whether or not you just want a power bank, or if you are willing to do a power bank plus a solar panel. From there, it is a matter of choosing a bank with the right level of power, and which panel might extend it to the duration of time you need. I personally would choose just a power bank, and charge it in town when you can. Unless you are not making frequent trips where you can recharge it, it will be simpler than dealing with the solar panel.

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