Small van solar power system

Hello I am exploring some power options for my 93 Plymouth Voyager. I don’t live in the van full time but camp in it most weekends and am doing a month long ski trip in Oregon next month. I am looking for a small solar power set up that will be able to charge camera batteries, a MacBook, a Bluetooth speaker, my phone and possibly run a boot heater to dry out equipment. Obviously not trying to run everything at the same time but looking for something that has enough power to run the boot heater and charge something for a night. The Voyager is not a very large van so something compact is a must. I have been looking into the Goal Zero Yeti 200x + Nomad 20 solar kit or the Jackery Explorer 240 with the SolarSaga 60w panel but am curious if anyone has any experience with either system.
Any advice or suggestions are greatly appreciated!
Thanks!

I don’t know about those kits, and you might get away with charging everything on your list with 60 watt panel, but likely not run the boot heater. Anything that produces heat will use a bunch of power.

You need to figure out an energy budget, meaning that you need to calculate how much power you need, and then come up with enough battery power and solar to meet those needs.

All of your chargers and appliances will be marked in terms of how much power they use. For example, your laptop charger may say 85 watts and your boot dryer may say 500 watts. A phone charger may consume 10 or 15 watts. DC appliances may state milliamp-hours or amp-hours instead of watts. There’s 1000 milliamps in one amp.

To come up with a number that you can use, you have to convert everything to the same units. Batteries are rated in amp-hours (amps in short), so it makes sense to convert everything to amp-hours.

For example, to convert what your 85 watt laptop charger uses in amps use Ohms Law to convert watts (power) to amps (current). 85 watts divided by 12 volts equals 7.1 amps. Then you’ll have to multiply the 7.1 amps by the number of hours you use it per day. Let’s say it charges for 3 hours a day, so that’s 21.3 amps per day.

Now let’s assume in the laptop example that your battery has a capacity of 50 amps, and your solar panel is 60 watts. The battery only stores power, but has to be kept charged. Without charging, your battery can power your laptop for a little more than two days before it needs to be charged. It will go dead after two days. You have to supply enough charging capacity to keep it charged, and enough charging to cover all your needs on a daily basis.

You spoke of a 60 watt solar panel. 60 watts divided by 12 volts equals 5 amps. Let’s say you get 6 hours of uninterrupted sun on your panel every day. That’s 30 amps. So with a 60 watt panel you’ll have enough to power the laptop indefinitely as long as you’re always in the sun, and you don’t have more than one cloudy day every 6 days or so.

Charging always takes a little more power than the battery can give, so 30 amps is probably the minimum you’ll need for the laptop.

Do these calculations for everything you plan to use to establish a power budget.

Also, powering things with 12 volt DC (no inverter) is far more efficient than converting 12 volts DC to AC. Inverters can suck a lot of power. It’s easy to supply 12 volt charging for phones by using USB adapters such as the ones used with a cigarette lighter. Same with the laptop charger - get a car charger for the laptop.

Also keep in mind that lead-acid batteries such as flooded, AGM, and Gel batteries can only supply about half of their rating before you start damaging the battery. For example, a 100 amp AGM is really only a 50 amp battery. If you need 100 amps, get 200 amps worth of batteries. Lithium is better in this regard - about 80% vs. 50%.

Maybe I’ll stop spending my valuable time trying to help. Hard to justify when there’s not even a thank you, comment, or question.

I appreciate you posting Axel! It’s not only the OP who gets to learn from your posts. Thanks :grin:

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Thanks Marty…