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I have 400aH worth of lithium batteries and 600 watts of solar (not laid out in an ideal configuration down the sides of the roof on my airstream).

I have found I use 60-90watts AC to power my starlink.

I can easily go all day even with 2-3 laptops and external monitors (150 watts or so). The solar keeps up and even does a little charging during the day.

Every other day when it’s cloudy or rainy I will need to top up with the small generator but that is easy to do with lithium batteries since they charge at the full 120amps unlike lead acid that taper the current significantly.



The one thing that bothers me about having all that pricey gear on an RV is what keeps people from stealing your panels, starlink, etc from a remote primitive site?

I mean some people will be using the RV for work, so will be present a lot but for the folks that park and go hiking or fishing a lot, what then? Some folks will handwave this away but we've had a lot of break ins at local boat landings. I can only assume the primitive camp sites are similarly vulnerable


You would need to mount it in a way that someone couldn't just come along and pick it up and go. Any mounting solution that requires internal access to undo would be a further deterrent.

Cameras would help too, and if you have either a very strong router (like a Ruckus), or cellular service, you could even potentially get notifications from the camera, prompting you to walk back because someone is attempting to unmount your stuff. Even just talking through one of those doorbell cameras will probably make them scurry off.

Even if you just slapped a simple chain bike lock on everything before you walked away that's probably going to stop most if not all attempts at stealing your stuff.


Most new RVs these days come with panels, they're screwed into the roof. Could you steal them? Sure, but it's probably more of a pain than the panels are worth. The Starlink is a different story, perhaps. Mine will be mounted on a pole attached to the RV, and taken off for travel anyway, so if I leave the RV unattended for any length of time I'll just stow it.

Battery theft is definitely a real thing these days, too, especially with expensive lithium batteries, so mine are in a lockbox to deter casual theft.


Did you study electrical engineering? Can you recommend a laymans resource for getting smart on how you did those calcs? For example I’d struggle to figure out the battery size for a given wattage / amp of draw.


Not the commenter, but it’s fairly straightforward.

I’ve actually made a simple calculator[1] for this, but you don’t really need it.

What you want to do is get a good picture of your actual usage per day in kWh. You can use a Kill-a-Watt plug or similar (a device that kWh that pass through it).

Once you have your daily kWh use, you can multiply by however many days you want to run without charging the battery. A lot of off grid solar people go for 2-4 days.

That gives you the useable battery size in kWh you need.

LiFePo4 batteries (arguably the best for this setup) typically have 80-90% useable capacity. Lead acid (the more traditional kind) have around 50%.

Adjust for that and you know what size of battery to buy.

A lot of batteries are defined as Amp hours and voltage. Multiply them together to get watt hours.

Max_kWh = (Ah * V) / 1000

Useable_kWh = Max_kWh * useable_percent

[1] https://uplevelgreen.com/off-grid-solar-calculator


Awesome thank you.


I got my ham radio license in March and I learned a lot about practical electricity while studying. Might be worth checking out some of the YouTube videos to see if it's up your alley.


I recommend Will Prowse on YouTube, he has tons of good content on DIY solar systems including sizing your array and battery bank.


Thanks!




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