New member

fabiangomez

New Member
Joined
Aug 1, 2021
Messages
13
Hey folks, just wanted to introduce myself and share a little bit about my situation. I'm from Houston and an ex IT tech who now does real estate photography and loves to bbq.

So my family and I will be soon moving to a new to us 2007 Dutchmen Victory Lane Toyhauler 36SRV-H5. We were not quite ready to move into a home yet as our financial situation is not where it needs to be quite yet to make that possible. So because we need to leave the small apartment we are in now, we decided that we had to make this move. All this came as a rather short notice decision unfortunately beyond our control. We have decided that since we own a SUV and not a large truck that has an appropriate hitch, later on down the line we will have to purchase a new truck as well so for now we will be using a transport service to relocate the 5th wheel to an RV storage for a month for us to make any needed upgrades or repairs and do a thorough cleaning to our liking. After a month or so we will be moving it to an RV park once they have a slot open for us. The RV world is a whole new concept to me and I've been doing my best to try to learn as much as I can in a short amount of time to get better familiar with everything that this new lifestyle will entail. One of my methods of learning about this process was via Youtube where I came across Will Prowses' videos and they have been a big help in regards to the idea of adding solar to my RV. I'll admit I really like the idea about using the sun to help offset some of the electricity costs we will incur as it's always very hot and humid here in Houston and being a family of 4 with a two and six year old we have our hands full and any savings will help. I've already done an energy audit and determined what we are willing to live without and what we can cut out. I used the Kill a watt meter and found that the bulk of my energy costs will be coming from a/c, freezer, refrigerator. Knowing this we couldn't really find a way to build a system around that initially using minimal solar so we might wait on that until we can afford it properly.

I've been making some goals for my RV and making a list of what I would like to add and accomplish to make those goals work. Initially we will be on shore power 100% of the time and won't be using the 5500w Onan generator onboard unless absolutely needed during power outages. I also have a separate Sportsman 3500w generator I purchase last year during the winter storm here that I can use as secondary backup.

My goals are that I'd like to have a rather nice size solar system to eventually be completely off the grid and only have to pay the rent costs at the RV park which do include water, sewer and wifi. That would really help us out financially but I know that the initial start up costs for that can be high and we might not be able to do that first thing. I'm ok with that and would rather be focused on one thing at a time and have a good order of operations setup to not waste money and be as efficient as possible working within my small budget.

In regards to the solar system setup, I've gathered that I have a few choices to make and that those choices are completely dependent on what my needs/wants and budget are going to be. That being said I have a few questions in regards to how to make those decisions as I'm not experienced with RV life. I'll begin with a few basic questions I have.


1. Regardless if my ducted a/c is 13.5 or 15k BTU, the general consensus I've come to based on the many conversations that I've had with other RV owners currently living at the RV park is that they are loud, expensive, inefficient, high wattage and not the best way to cool an RV. They say that even running 2 a/c units in the RV park that has zero trees it can still get warm inside in this Houston heat. Knowing that I've decided that my best bet is to install a mini split system something like this Pioneer unit. My question is, how can I determine the correct size of a mini split system based on the dimensions and odd shape to my toy hauler? In our configuration we would be converting the back 12x8 storage to a kids room. We even considered installing a window unit if it would use less power than the onboard a/c.


2. If we are on shore power 100% for at least the next 2 years, do I need a transfer switch? My very basic understanding is that they redirect power depending on where it's coming from. That's great but if for now it only comes from the pedestal unless there is a power outage and I have to swap to one of the 2 generators, one is onboard and one is simply switching the power plug location. I don't know if I even have one, but because there is a onboard generator I think it's at least a possibility. Now years from now when I do get a solar system I can see how I would want to switch from solar power to shore power as needed and if the transfer switch will be needed for that then so be it at that time.


3. If I plan on even just getting one LiFePO4 battery, I would need to change my current converter/charger to a Lithium compatible multi stage one correct? The way I understand it is that when connected to shore power the converter is constantly running making it possible to use my outlets in the RV. It makes sense that if later in the future you plan on going the solar route that your options open up to include a hybrid inverter/converter/charger/switch so you might not want to waste money now on something you would be bypassing later. I get those are costly but it seems they have the most versatility, but if you are years away from that and want the lithium benefits that might not really be beneficial to you since you are on shore power, then you can just wait all together until you need it?


4. There is a modular solar build and an all in one method. Modular buying all the individual pieces needed to complete the same goal as a let's say MPP Solar or Growatt all in one system. In regards to value, the all in one seems the clear winner, but obviously the modular route has it's many benefits. I can't seem to find a single person or video that has somehow made one of those work in an RV scenario using a 50amp RV pedestal connection when on shore power 100% supplying 120 to each leg. Clearly those seem to be geared towards off grid and boondocking, but if I eventually wanted to still be on shore power and just have solar as a supplementary system to help keep my bill low, how would one go about integrating the solar/grid lifestyle with one of those devices? The only unit that seems to have solved the 50amp/2x120 issue is the Victron Multiplus 2 using both legs. I just can't afford that $1,500 cost when the all in ones are $700 if they can be made to work the same way, which I don't know if they can that would be great for me.


5. Would it be cheaper to just build an all in one system on a hand truck vs bothering with integrating the solar system into the RV electrical system if you really only plan on using the solar to run a mini split, window a/c's, freezer or say a computer system? I understand that whatever you plan on running with solar you would have to have enough solar coming in, battery bank to store it and inverter to make it work and draws need to meet the spec and stay under the amp/watt loads. It just seems like the preferred way with electrical integration is many thousands more and only worth it for not having an eyesore hand truck or milk carton in the underbelly.


I understand that many of these questions might be absurd, dumb, or ridiculous to some, but honestly these are things I know nothing about. I have been diving into this topic for months now and at first it was very intimidating, it still is. I'm only slowly now starting to understand a little more and feeling more confident in asking for help and advice. It's taken time to digest what I've learned to barely be able to express what I'm still confused and ignorant on. I can openly admit that I'm bringing a student mentality to this and want to learn what I need to so I can make all this work for me and my family. Budget is the largest issue currently for my RV goals and needs which is why I want to not make any mistakes with wrong purchases and overspending. Any advice, help, suggestions or respectable open lines for dialogue are greatly appreciated as I have seen this community is composed of very knowledgeable individuals. Thanks for your time.
 

Greendream

Off-grid Beginner
Joined
Jun 30, 2021
Messages
67
Location
Colorado
I am new so I can't answer a lot of your questions but let me give you some insight that ive gained.

For off grid you really gotta think of conservation. The more power demands you have such as microwaves or AC use after dark requires a big battery bank. To fill that bank the next day you need enough panels for your location and time of year to recharge. All of this is big bucks for real. 1500 or 800$ is nothing after its all said and done.

We are living in our RV while we build our home. 4k of panels and 345AH of 48V LFP is barely enough to keep up with our AC. If we wait until its 85F and run it down to 80F we can sometimes keep up. A hot day here is 95-100F. Your thought of a mini split is a better choice. The amount of money it takes in hardware to run these high wattage ACs doesn't seem worth it to me. Investment in insulation would be a good idea especially if you'll be parked for a while. We don't expect to have these power demands once the house is built since we wont need central AC.

We have a shed with our batteries, inverter/charger and AC breaker box. There are 30A receptacles we plug into for shore power.

We've had our batteries go into low voltage shutdown twice and suffered with the heat one day in the past 8 weeks or so. If you'll have shore power as a backup you wont have any of these problems but if you don't have enough solar for the AC you'll be spending money there.

I have a magnum inverter with the mini panel. Its setup with a switch to bypass the inverter for our generator, a grid tie would be the same.

You'll need to see what charge controller is already in your camper. LFP uses CC/CV or an LFP preset from the charge controller and the BMS handles the charging of the cells in the battery.

The cost of off grid setup is spendy but so is grid over time If this is your plan why not go after it now versus later? You'll have the upfront cost but no grid bill ever again.

How much space will you have at the RV park for panels or will they be mounted on the roof? Can you have a shed?

If you just want it for supplemental power or if grid goes down you can build a smaller system to run everything but microwave and AC. Use the grid for AC.

We never run our generators anymore thankfully. We were using about 7 gallons a day with AC running our onan 4kw before solar got setup. Over $600 a month for fuel.

Best of luck wish i could answer more questions.
 

chrisski

Solar Boondocker
Joined
Aug 14, 2020
Messages
3,386
Welcome.

Really recommend you look at the DIY Solar Blueprints in the link up top.

If the goal of the system is to save money and stay at an RV park and save money using solar, not sure how that would be done. I’m not sure with what your asking how it would be possible and cost effective.

I’m not sure purchasing a mini-split at the cost of $900 installed yourself will cover any money saved from utility bills. That big noisy unit is probably a 15k BTU air conditioner, but the min-splits top out at about 12k BTU. A window AC may be purchased cheap, but is only 5K BTU, which could be good for a room. If you have a 15K BTU AC, you probably need to replace it with a 15k BTU AC.

I can only say get to know your RV and how it uses the AC before making any purchases. My 15k BTU AC in the RV when the the temp is 90 out, will be running non-stop When set to 78. I need to work on insulation for it to get any better. The only 110 volt mini-split I found was 12k BTU. If all I did now was swap the AC, I would be hotter than I am now.

I’ve come up with no good way to integrate solar and grid power in my RV. FOr me its either I’m Boondocking with no AC in good weather making all the power I need, or I’m hooked to shore power not using the solar panels on my roof, but the park is giving me the power to run the AC. Actually at the RV park me not using the solar is not entirely true. I do use the solar panels to run all the 12 volt items like the lights and phone chargers, but that is really nothing at all compared to what the AC uses.
 

fabiangomez

New Member
Joined
Aug 1, 2021
Messages
13
I am new so I can't answer a lot of your questions but let me give you some insight that ive gained.

For off grid you really gotta think of conservation. The more power demands you have such as microwaves or AC use after dark requires a big battery bank. To fill that bank the next day you need enough panels for your location and time of year to recharge. All of this is big bucks for real. 1500 or 800$ is nothing after its all said and done.

We are living in our RV while we build our home. 4k of panels and 345AH of 48V LFP is barely enough to keep up with our AC. If we wait until its 85F and run it down to 80F we can sometimes keep up. A hot day here is 95-100F. Your thought of a mini split is a better choice. The amount of money it takes in hardware to run these high wattage ACs doesn't seem worth it to me. Investment in insulation would be a good idea especially if you'll be parked for a while. We don't expect to have these power demands once the house is built since we wont need central AC.

We have a shed with our batteries, inverter/charger and AC breaker box. There are 30A receptacles we plug into for shore power.

We've had our batteries go into low voltage shutdown twice and suffered with the heat one day in the past 8 weeks or so. If you'll have shore power as a backup you wont have any of these problems but if you don't have enough solar for the AC you'll be spending money there.

I have a magnum inverter with the mini panel. Its setup with a switch to bypass the inverter for our generator, a grid tie would be the same.

You'll need to see what charge controller is already in your camper. LFP uses CC/CV or an LFP preset from the charge controller and the BMS handles the charging of the cells in the battery.

The cost of off grid setup is spendy but so is grid over time If this is your plan why not go after it now versus later? You'll have the upfront cost but no grid bill ever again.

How much space will you have at the RV park for panels or will they be mounted on the roof? Can you have a shed?

If you just want it for supplemental power or if grid goes down you can build a smaller system to run everything but microwave and AC. Use the grid for AC.

We never run our generators anymore thankfully. We were using about 7 gallons a day with AC running our onan 4kw before solar got setup. Over $600 a month for fuel.

Best of luck wish i could answer more questions.
That sounds like a good size system, 4k watts. I had imagined I’d build a 2k watt one and that it would be plenty but I can see I was wrong. I’d heard around 700-800AH is pretty nice but I can see how that can get expensive real quick. I was thinking eventually one day going 24V for wiring purposes. I agree that doing it now would be fantastic cost wise in the long run, I might do that if I can make the MPP solar unit work as it’s the cheapest option especially since I’m noticing these batteries go for as low as $399 now. Depending on which RV park I choose to go to, one has no space for panels and I’d have to mount on the RV rooftop, the other lets you have a storage shed so I could build something nice, but RV mounting appeals to me more so I can relocate it in the future easier. Yeah I agree, maybe run the mini splits/window units off grid and just everything else off solar until I can build something big enough to actually make a difference in the electricity bill by helping with the a/c costs. Yeah during the storm here it was getting expensive filling up with gas often. It’s ok, thanks for taking the time to reply, I appreciate it.
 

fabiangomez

New Member
Joined
Aug 1, 2021
Messages
13
Welcome.

Really recommend you look at the DIY Solar Blueprints in the link up top.

If the goal of the system is to save money and stay at an RV park and save money using solar, not sure how that would be done. I’m not sure with what your asking how it would be possible and cost effective.

I’m not sure purchasing a mini-split at the cost of $900 installed yourself will cover any money saved from utility bills. That big noisy unit is probably a 15k BTU air conditioner, but the min-splits top out at about 12k BTU. A window AC may be purchased cheap, but is only 5K BTU, which could be good for a room. If you have a 15K BTU AC, you probably need to replace it with a 15k BTU AC.

I can only say get to know your RV and how it uses the AC before making any purchases. My 15k BTU AC in the RV when the the temp is 90 out, will be running non-stop When set to 78. I need to work on insulation for it to get any better. The only 110 volt mini-split I found was 12k BTU. If all I did now was swap the AC, I would be hotter than I am now.

I’ve come up with no good way to integrate solar and grid power in my RV. FOr me its either I’m Boondocking with no AC in good weather making all the power I need, or I’m hooked to shore power not using the solar panels on my roof, but the park is giving me the power to run the AC. Actually at the RV park me not using the solar is not entirely true. I do use the solar panels to run all the 12 volt items like the lights and phone chargers, but that is really nothing at all compared to what the AC uses.
Are those DIY solar blueprints the same as the one on will’s site? Those are awesome, I also like the EXPLORIST life blueprints. All those schematics are great for simple clear cut builds.

The goal of the system initially would be to enter the RV solar system market at the lowest entry cost. But build a system that allows you to scale with the addition of more panels or batteries. However I know that solar as a whole isn’t an inexpensive venture. I still need to narrow down how I can best create a system and use the system so that it could be of benefit realistically and cost effective. The two choices seem to be run everything else in the RV off of solar which isn’t much and isn’t even the bulk of the electricity usage. In that scenario the initial cost of all the solar gear wouldn’t seem worth it if it’s only going to save you a couple bucks from cell phone chargers and maybe a tv or xbox. Getting a system up and running for a/c would handle 90% of the electricity bill but I understand we are talking big bucks to do that, not ideal at the moment. So what if I can put together something that helps like 50% of the way and uses the sun to help power the electric load in the daytime, and battery power at night, and when those are depleted use the grid. Or use both at the same time if needed depending on loads.

My initial theory for why the mini split unit might help me save money on my electric bill was because when I used the kill a watt device on my window unit it averaged 550 watts where as I’ve seen RV rooftop unit use like 1300 watts. I thought that difference and the efficiency rating in the 20’s of those Pioneer mini splits that use 300 watts would be worth it. I know the a/c in the RV is a 13.5 BTU and the RV is a 36ft monster. It made sense that the mini split would do a better job at cooling, and yes the 5k window unit would go in the kids room if I don’t install a small portable unit instead.

I agree that I should live in it a while and monitor the usage, cost and comfort level the stock a/c unit delivers.
 
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