Reddit reviews X-DRAGON Solar Charger, 40W Solar Panel Charger (5V USB with SolarIQ + 18V DC) Water Resistant Laptop Charger Compatible with Cellphone, Notebook, Tablet, iPhone, Android, Camping, Portable Generator
We found 3 Reddit comments about X-DRAGON Solar Charger, 40W Solar Panel Charger (5V USB with SolarIQ + 18V DC) Water Resistant Laptop Charger Compatible with Cellphone, Notebook, Tablet, iPhone, Android, Camping, Portable Generator. Here are the top ones, ranked by their Reddit score.
☀️Exclusive SolarIQ Technology: With built-in smart IC chip, automatically adjust the current and voltage to achieve maximum power,delivering idealcurrent up to 2.8A under direct sunlight☀️Ultra-High Efficiency: Built with US SUNPOWER solar cell, 22%-25% efficiency, 50%higher, compared to common panels, which are 15%☀️Dual-Port Output：USB port (5V/2A) for charging your 5V powered gadgets, and 18V DC output (18V/2A) for charging your laptop or other 18V powered devices☀️Water-Resistant and Safety Protection : PET solar panels with rugged high-wear Oxford fabric offer weather-resistant durability for any outdoor environments and activities. Surge protection, short circuit protection and more advanced safety protections keep you and your devices safe☀️Package Contents: 40W Foldable Solar Charger, 10 laptop connectors, DC cable, USB cables, carabiners, instruction, 18 months no worry warranty and brilliant customer service
You'd want to go straight from 12-18v. You can try a laptop car charger but I'd be kind of nervous of low voltage issues. I'm guessing the laptop charger will turn off when it decides it doesn't have enough power. From there it will either cycle on and off or stay off until you unplug it and plug it back in.
From there you might want to add a 12 battery in between the charger and panel, it'll need is own charger controller, we're adding weight at that point. I'd probably not bother with the battery, try the 12v laptop charger and if that doesn't work go with something like this:
https://www.amazon.com/gp/product/B01IQMAUSA/ref=as_li_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B01IQMAUSA&linkCode=as2&tag=tcb1050-20
*I think there's an affiliate link, it's not mine but the website that found it for me
I can't vouch for this, but here's what comes up at the top of an Amazon search for "solar laptop charger":
https://www.amazon.com/X-DRAGON-Charger-Sunpower-NoteBook-Smartphones/dp/B01IQMAUSA
Range is rated around 300 watt hours per mile divided by lets say 8 hours of sunlight means a 37.5 watt solar panel could give you a mile per day. This solar panel could give you a mile a day ignoring drain. It adds up, 4 years 365 days 8 hours * 40w = 467 kwh and that panels only 4 square feet. I want to say its 8-10 watt per square feet for a solar panel, probably slightly less embedded in glass. Need measurements on the Model S roof.