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A "panel + power station" semi-portable RV solar system. Thoughts?

helloterran

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Joined
Feb 28, 2022
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Hi guys, solar newbie here, recently found this forum and learned a lot!

I'm building a RV solar system to allow occasional work-from-roadtrip spanning 1-2 weeks at most. (I'm an IT professional). I primarily visit national and state parks. Would prefer boondocking but probably will visit full hookup campground once a week.

The current plan is to power every RV appliance either by the original in-house battery, generator or propane, and plug only work-related devices to the power stations.

In total I need to power:
2 17" macbook pros, 2 27inch monitors, 2-3 cellphones + booster, plus starlink (that's a constant power sucker!). All needs to be powered 8-12 hrs a day
So I need a lot of AH, but I don't need too much inverter power (the larger the inverter, the larger the idle draw).


The reason for going power station instead of battery+inverter charger+solar charger + alternator charger are (let me know if these analysis makes sense):
1. I don't want to drill too many holes on my RV shell
2. RV is old, investing too much on a dedicated rv system doesn't make much sense.
3. I want to be able to easily move the whole system to another RV in a year or so.


I recently acquired 2 Bluetti eb240 boxes mainly for my class c, and am looking for inexpensive 400-600w panels just to keep them charged on the road or at no-hookup sites. Any recommendation is much appreciated!
 
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Personally I think the power stations are the shiznit. I spent a lot of time effort and money upgrading my entire charging system and a DIY lifepo pack in a 17yo winnebago motorhome, and still bought a Ecoflow Delta Mini, just because they're so cool and so handy. And will power up way more than my 600w inverter can.

It's best to add up the running watts for your appliances and estimate daily running time to get a feel for how much energy you need to provide for them. Once you know that you'll know if your bluettis will provide that, and then design a solar panel system to capture that each day. As you say, you can always get to a RV park and plug in to charge everything back up.

A portable panel setup is do-able, I have two 80W 'suitcase' panels I can set out for portable power, either plug into the side of the coach to a mppt charge controller, or I can plug them into the delta and charge it. They store and deploy easily, about 25lbs, and 20x40 inches folded, so they fit in a basement compartment. However I can only get about 8amps from them.

Know that large wattage panels can be heavy and bulky. You'll need a way to store and deploy them. You may still be better mounting them to your unit's roof. If you use strut channel you can easily remove them if you get a new rig. You don't even have to mess with your 12V system, but I would encourage you to consider connecting them in to keep everything charged up.

I would recommend mounting your charge controller in the unit with a way to connect your bluettis. Make up a solar array that fits your charging needs, with a way to connect them to the controller. Anderson connectors are available in a bulkhead mount, so that might be a good option.

Once you know what kind of wattage you need you can choose a controller, and panel size to suit. 100W panels are a dime-a-dozen now, and there are some nice 150-200w options that might work as well. I put two 215W panels on my roof in series, feeding a Tracer AN mppt 30A charge controller. On average I get about 15-20 amps from them, or 200-250 watts. It's easy to compare watts cuz volts doesn't change them. Flat mounted panels never get you full utilization, but they're sure easy to deal with.
 
I have two 320 watt panels that I deploy on the ground when needed. They are a PITA to store and move around, but boy do they crank out some amps! I'm considering buying two more, because I'm a glutton for punishment and it's a good workout. My LiFePO4 system has been online for about 20 months.

I also have 640 watts of PV on the roof of the RV. Most of the time that's plenty of power. However, I'm bringing online a Victron Multiplus 12/3000 inverter that will power more stuff in my RV like the microwave and maybe the air conditioner. The PV/LiFePO4 bug has bit me hard and I want more. At least enough that I don't have to fire up the generator.

I'm in IT also and plan to hit the road while still working full time and then eventually part time. I avoid campgrounds like the plague. I can boondock for about 10 days. My limitations are the black and gray water tanks.
 
Personally I think the power stations are the shiznit. I spent a lot of time effort and money upgrading my entire charging system and a DIY lifepo pack in a 17yo winnebago motorhome, and still bought a Ecoflow Delta Mini, just because they're so cool and so handy. And will power up way more than my 600w inverter can.

It's best to add up the running watts for your appliances and estimate daily running time to get a feel for how much energy you need to provide for them. Once you know that you'll know if your bluettis will provide that, and then design a solar panel system to capture that each day. As you say, you can always get to a RV park and plug in to charge everything back up.

A portable panel setup is do-able, I have two 80W 'suitcase' panels I can set out for portable power, either plug into the side of the coach to a mppt charge controller, or I can plug them into the delta and charge it. They store and deploy easily, about 25lbs, and 20x40 inches folded, so they fit in a basement compartment. However I can only get about 8amps from them.

Know that large wattage panels can be heavy and bulky. You'll need a way to store and deploy them. You may still be better mounting them to your unit's roof. If you use strut channel you can easily remove them if you get a new rig. You don't even have to mess with your 12V system, but I would encourage you to consider connecting them in to keep everything charged up.

I would recommend mounting your charge controller in the unit with a way to connect your bluettis. Make up a solar array that fits your charging needs, with a way to connect them to the controller. Anderson connectors are available in a bulkhead mount, so that might be a good option.

Once you know what kind of wattage you need you can choose a controller, and panel size to suit. 100W panels are a dime-a-dozen now, and there are some nice 150-200w options that might work as well. I put two 215W panels on my roof in series, feeding a Tracer AN mppt 30A charge controller. On average I get about 15-20 amps from them, or 200-250 watts. It's easy to compare watts cuz volts doesn't change them. Flat mounted panels never get you full utilization, but they're sure easy to deal with.
Thank you for your detailed input!

The only calculation I did sofar told me I'll need about 200AH battery per work-day with heavy use and safety margin in mind.

I have mostly decided to go solar: the power stations come with 200w charger and the max DC or PV input they accept is about 500w, which still takes about 6 hours from 10% to top off. Since the charging speed is so slow, it doesn't make sense to use the generator. I'll either have to find a power outlet every 2-3 days, or rely on solar for the boondocking days. I'd of course prefer the latter.

Like you mentioned, rigid panels of the right size (400-600w, max 60V 10A, ) would weigh aound 50 pounds or more. Portable panels are lighter but also less efficient so I'll need more of them. Being as lazy as I am I don't think I'll enjoy moving them in and out everyday plus setting up all te wires. Also using portable panels means I cannot charge on-the-go. This kinda defeats the purpose for me.

The minimalist way for my solar setup would be to just mount panels on the roof and get the MC extension cord into the cabin. I'll just use the bluettis' built-in mppt controllers. The most difficult part I think, would be the wiring from roof and brackets for the bluettis
 
I have two 320 watt panels that I deploy on the ground when needed. They are a PITA to store and move around, but boy do they crank out some amps! I'm considering buying two more, because I'm a glutton for punishment and it's a good workout. My LiFePO4 system has been online for about 20 months.

I also have 640 watts of PV on the roof of the RV. Most of the time that's plenty of power. However, I'm bringing online a Victron Multiplus 12/3000 inverter that will power more stuff in my RV like the microwave and maybe the air conditioner. The PV/LiFePO4 bug has bit me hard and I want more. At least enough that I don't have to fire up the generator.

I'm in IT also and plan to hit the road while still working full time and then eventually part time. I avoid campgrounds like the plague. I can boondock for about 10 days. My limitations are the black and gray water tanks.
Thank you for your detailed list. I'm OK with running my Onan for 10-20 min a day just for the microwave (it keeps the generator healthy and charges the SLA battery somewhat). I try to avoid visiting places that require AC all-day . I'm also limited by my 22 gal grey water tank if I'm not working, and with strict navy shower it can last 3-4 days for the 2 of us. However finding a dump station is still easier/cheaper than a hookup site.
 
Funny, I'm IT too. :rolleyes: ?

200W panels aren't as bad (30lbs), but you still need to store them on the go. They're big. IMO grid-type PV's, like the 300-400w ones are not portable friendly at all. And don't forget if it's windy you need a way to tie them down. Not terribly difficult, but one more thing to contend with. The big advantage is being able to point them right at the sun. And yes, can just plug into the bluetti units.

Roof top are pretty easy, depending on your roof structure. Strut channel has gotten pretty popular, makes them easy to remove and service.
Run the wires down the refer chimney, or just put a glands type through box and run the wires down a closet or cabinet or something.

Some will mount tilt-up panels over a back or side window.

Watch your Voc volts on panels in your planning so you'll know whether to wire in parallel or series, based on your charge controller. The Victron stuff is really nice, a lot of us get by with the EPEver ones as well.

Building a jig to hold your power banks shouldn't be too difficult - even thru-bolt cargo loops on the floor and a ratchet strap would do it. Or a wooden frame they set into that can be tied down.

Let us know what you find as you round out your list.

Here's how I did my panel mounting:

IMG_4078.HEIC
 
I just looked up the eb240 specs - 200W charging - wow! My delta mini will take 900w, charge up in an hour. So if I fire the onan it will charge really quick. Same for my house bank - 55A charger brings up the 230A battery pretty quick. For a 2.4kW setup that seems like a slow way to charge. [shrug]

PV max input: 500W. I would shoot for 600w of solar - 400 on the roof and 200 deployable, for example. A folding pair of 100W panels might work out nicely. And it shouldn't be too hard to find room for a couple of 200W for the roof. If you have room a pair of 150W folders might work too. Just rivet hinges on them and bolt on aluminum L-legs. They can lay on a mattress for travel.

If it's hot out we run the gen for AC anyway.

I was looking at the EB150, then the EB70S with the extra 100W of AC output, but then got swept up with the Ecoflow Delta units.
 
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