How long to charge?

How do I determine how long it will take to solar charge my system?
I found a worksheet that said the most I’d use per day is 248 amp hours per day.
This person’s worksheet suggested I have 400 amp hr lithium or
|AGM Batteries|700 Amp Hours|
|Solar Panel Array|800 Watts|
|Inverter|3000 Watts|
So do I really need that much solar system? Is that so that I could go several days without recharging of any kind?
THus my question how long would it take to recharge? I spend a lot of time in the PNW where it is overcast ALOT!
THANKS for the feedback and instruction in advance. I’ve learned so much thru the course and you feedback…


Solar is terribly inefficient, and I sure wouldn’t rely on it in the PNW. Typically for 700ah of batteries, you would want at least 1400 watts of solar, and 2100 watts would be preferable.

238 amps per day is a LOT of power. My measly 100ah lead acid deep cycle battery will last me a week! It’s a much better practice to conserve power than to create more of it. I don’t even normally use an inverter for anything, and I just charge my house battery while driving, no solar needed.

Heating, cooking, hot water, and anything else possible should be run on fuel, not power. A/C’s require either shore power or a generator, but a swamp cooler will work great & be energy efficient. My swamp cooler uses only 2 amps @ 12vdc on high, and a little under 1 amp on low which is usually where it’s set at.

I charge my house battery and electronics when driving, which gives me one free charge on everything without using the house battery to charge them.

About the only thing I don’t have is a microwave, because it takes up too much space, and really isn’t needed. I can heat anything I want on my stove or in my oven. I can cook anything you could cook in a house in my camper, and I enjoy eating well. No rice & beans for me!


"Be the reason someone smiles today!" ~ Van_Dweller

I live in the PNW…. Just not the area that rains 9 months of the year. But if I did, probably wouldn’t rely on solar. Many other places where it’s sunny at least every couple days might provide some adequate charging, provided your not parked for days on end and solely relying on solar to recharge your batteries, unless of course you reduce your reliance on electricity. I use a DC/DC 30 amp and it juices those batteries pretty quick with the 400 watts of solar to recharge 340 amp hrs of lithium. I can recharge with a mostly sunny day and a few hrs of driving from about 60% +.

I currently park in a mostly sunny part of Washington ( the PNW) that experiences 300 days of Sun, so it’s not the same issue as Western WA. I think like van dweller said I would find a way to reduce your consumption on power from battery only if your going to reside where it rains nine months of the year ha ha . And then maybe you’ll be less needful of excessive solar. But a DC to DC charger… I believe is the best way to get those batteries recharged or just have a place to connect to shore power.