Inverter vs solar generator

[Acga1]

Thank you very much for this information. I’m at a loss on this. I’m trying to figure out the best solution
Our camper is set up for 50 amps. 2 AC’s and wiring for a dryer.
Dryer we will never install.
AC’s I see us really using the main unit and alternating if needed to run the master.

I’m not looking to run the AC for hours on end. This is a weekend/vacation setup for us so having the ability to run it for long periods of time is not to crucial.

Following is what I have in camper:
2 AC’s: 1-15,000btu and 1-13.5btu
Electric fireplace: 12amps or about 1465 watts
Microwave: about 1350watts
Occasional coffee pot use at 1520watts
Misc tv’s +\- 108 watts

We know this will take some learning as we would have to maybe turn an item off to use another. Say the AC is running, we might need to shut it off the run the microwave, etc.

Speaking of batteries: we have 1 for the 12v side of things and want to upgrade those as well. Have no idea which brand/ style is good for that. Camper does have 1 solar panel for the 12V battery which is currently installed.

Hit the post button to soon:
Attached is the charge controller for that panel.

How does the hybrid system work?

Our ultimate goal is to be as self sufficient as possible and not have to rely on a generator running every time we go…

At first I was planning on just a decent generator. Maybe 2 champion’s with the 50 amp parallel setup. I was going to build an enclosure to help with the noise.

Thank you again for your time in responding. We’re new at this and want to have it set up right so we don’t have to be filling gas or propane every weekend.

 

[Rich W.]

You mentioned that this unit will stay at your vacation property. This gives you a significant advantage if you seperate the RV from your off-grid power solution. A simple ground mount solar set-up in the 5-6kw range will run everything when the sun is shining, and a small battery back-up will get you through the night, as long as you rely on propane for heat. If you find the battery bank isnt sufficient during extended periods cloudy weather you can just add on to it as you go, but you probably wont be using air conditioners on those days.

RV solar is typically more complex, always limited, and usually much more expensive than residential. For 20 years I ran a large battery back-up system with 16 GC2 batteries and two 5.5 kw zantrex inverters so I could run all my 240v appliances including the well pump. I could run the whole house for three days during a power outage without running the generator. I had a 15kw propane generator but it used a lot of fuel and we often had trouble getting deliveries in the winter. This was a large and fairly inexpensive system, but you’d never put it in an RV.

So back to a solar set up, if you are interested I can send you some basic specs, and since you are not going to connect to the grid you can do it with no permits or inspections. Just make sure you have competent help. If you want I can send you approved plans ( in Ca so totally over built) for a 10kw ground mount system and you could just downsize to meet your spec.

Also be advised that solar panel prices are rising very wuickly right now so plan to spend .33+/watt for chinese panels and close to .60 for premium panels such as LG. For your purposes the chinese panels should be technically sufficient.

As for the OEM solar stuff, you will probably either end up removing it, or just leaving it unused in place. Its set up to keep your house battery topped up but thats all it can do. It wont be part of your off-grid power solution. Just think of it as a mobile 30amp (max) battery charger.

 

[Rich W.]

First pic below is an RV mounted system that would run one 15k btu AC all day on a sunny day and around 4 hours after sunset. The inverter was $1400, the charge controllers $300 each, and the battery banks were salvaged from a Nissan Leaf. This RV didn't come with a transfer switch and this picture was taken with the cover off the after market switch for whatever reason. Pictures 2 & 3 are the same basic system with more battery mounted in my Bay Star.

I probably had around $1000 - $1500 in those batteries, but prices have gone up considerably since people “discovered” these batteries have other uses. They also require special handling (monitoring, equalizing, charge and discharge limits, temp control, etc) for safety and longevity because they are just the li-ion modules (2 cells each). For comparison, the big bank pictured (24 modules) is equal to about 3 1/2 Titan battery modules, which would cost around $1400 each.

The system in the first picture was all under the dinette seats in a 30’ Fourwinds class C. Pictured is one battery bank and the hardware. Another identical bank was under the other seat. It also had 1875w of LG panels on the roof.

I’ve designed a system that will run both ACs on my Ventana that includes a Victron 48v 8kw inverter ($1800) and 28 Leaf modules (probably another $2000+) and 5 315w panels (currently installed). Also the Leaf battery modules in the system pictured were 2013 gen 2. They have more than doubled in capacity since then and are now on Gen 4. Im always watching for gen 3 or later now.

I might not ever build this system because it is really just an expensive hobby - not cost effective at all as SaltyVet pointed out. Right now Im just running my 5 panels as a big battery charger for my OE lead acid batteries with two 150/35 victron controllers on the Ventana and of course no hope of running an AC. I have repurposed the old modules in my Polaris Ranger EV.

 

[Acga1]

You mentioned that this unit will stay at your vacation property. This gives you a significant advantage if you seperate the RV from your off-grid power solution. A simple ground mount solar set-up in the 5-6kw range will run everything when the sun is shining, and a small battery back-up will get you through the night, as long as you rely on propane for heat. If you find the battery bank isnt sufficient during extended periods cloudy weather you can just add on to it as you go, but you probably wont be using air conditioners on those days.

RV solar is typically more complex, always limited, and usually much more expensive than residential. For 20 years I ran a large battery back-up system with 16 GC2 batteries and two 5.5 kw zantrex inverters so I could run all my 240v appliances including the well pump. I could run the whole house for three days during a power outage without running the generator. I had a 15kw propane generator but it used a lot of fuel and we often had trouble getting deliveries in the winter. This was a large and fairly inexpensive system, but you’d never put it in an RV.

So back to a solar set up, if you are interested I can send you some basic specs, and since you are not going to connect to the grid you can do it with no permits or inspections. Just make sure you have competent help. If you want I can send you approved plans ( in Ca so totally over built) for a 10kw ground mount system and you could just downsize to meet your spec.

Also be advised that solar panel prices are rising very wuickly right now so plan to spend .33+/watt for chinese panels and close to .60 for premium panels such as LG. For your purposes the chinese panels should be technically sufficient.

As for the OEM solar stuff, you will probably either end up removing it, or just leaving it unused in place. Its set up to keep your house battery topped up but thats all it can do. It wont be part of your off-grid power solution. Just think of it as a mobile 30amp (max) battery charger.

Thank you Rich. If you don’t mind sending me some info I would greatly appreciate it.

 

[Rich W.]

Plans sent via PM - let me know if you have any questions.

Once you digest all this you might find that SaltyVet’s hybrid idea is best. If I were doing this it would include a 4kw generator in a well insulated shed for running ACs and charging batteries, along with 4-6 AGM GC2 batteries and a 2kw inverter for overnight and misc daily use, and 2-3 residential panels on the shed to keep the system charged when the sun is shining. And you could always add to it if you found you needed more battery or solar power.

 

[SaltyVetAdventures]

Plans sent via PM - let me know if you have any questions.

Once you digest all this you might find that SaltyVet’s hybrid idea is best. If I were doing this it would include a 4kw generator in a well insulated shed for running ACs and charging batteries, along with 4-6 AGM GC2 batteries and a 2kw inverter for overnight and misc daily use, and 2-3 residential panels on the shed to keep the system charged when the sun is shining. And you could always add to it if you found you needed more battery or solar power.

Rich has some great ideas. But they aren't always cheap ideas. I guess we really need to know what your budget is before any actual advice.

If you do go with a large ground mounted solar array then I would get the panels from Santan Solar. They sell used commercial panels that are about 3-5 years old. When the life span of a solar panel is 20+ years...that is a great deal. You can get used 300 watt panels for $100 or so each. Since they are used, they aren't allowed to be used in grid tie applications but since you are 100% off grid, no problem.

No matter what you do, at least have a small generator as back up. Rich sounds like he has some great solar ideas. Good luck!