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diy solar

solar questions, new rv user

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.
 
A lot going on there.

I’m concerned about your portability and how you can transcend your situation. The RV can be a very stopgap and part of an escape plan. However, how can you manage things such that you don’t get trapped into your self-protect mode ?

I’m genuinely concerned- not criticizing; I know about tough times. And I know about escaping the trap, too.

By planning to buy a truck to make your RV portable sounds like a possible trap. A tow rig is a large expensive proposition. (I get the truck so I can make the RV portable, but the expense forces me to sustain the RV because I can’t afford to normalize my living situation)

Solar is great in so many aspects. Even when broke sometimes. If you can enable a recovery plan without overspending on the RV (one or two month break-even) then maybe it’s worth it. If not a short return term for buying solar and gearing up then you really got to ask yourself what’s best for your family in. Few months sure, but by then you should be socking money away to rejoin normalcy
 
bump. still need those questions answered if anybody out there knows. thanks in advance.
 
question 1 AC

HOw much are you willing to spend to save a couple hundred a month? A new mini system lit AC from Amazon may run $1.5k, but only a 9k BTU is available at 110v. So three of those will get you to the point of where you’re at now with a 15k and 13.5k. Add to that about 6kw panels and perhaps you have the power to run that. I estimate it would take me$20k and a trailer to build what you’re adking
 
1. Check the Mini-split specs for suggested number of square feet that it can cool.
2. If you're on shore power you don't need a transfer switch. If you have an on-board generator already then there is already a transfer switch installed.
3. The converter charges the 12v system, not the 120v AC system. Therefore, your outlets do not use the converter. The lights, fans, pump, etc do use the 12v system and that's where the converter comes in. I chose to replace my converter for one that understands a LiFePO4 charge profile. Since you're going to have your converter on all the time (while on shore power) I would absolutely get one with the right charge profile, but not until you have the LiFePO4 battery or batteries installed.
4. The typical inverter/charger that most of us are putting in our RV's would not understand that you want to use solar first and then shore power.
5. The components most likely need to be indoors, not exposed to the elements. But you can create a system that doesn't fully integrate with the RV. Look for threads started by forum member @Firetodd . He just completed an install like this.

Better to ask the "dumb" questions now, rather than later after you've started buying stuff or you've installed it and it doesn't work.
 
1. Check the Mini-split specs for suggested number of square feet that it can cool.
2. If you're on shore power you don't need a transfer switch. If you have an on-board generator already then there is already a transfer switch installed.
3. The converter charges the 12v system, not the 120v AC system. Therefore, your outlets do not use the converter. The lights, fans, pump, etc do use the 12v system and that's where the converter comes in. I chose to replace my converter for one that understands a LiFePO4 charge profile. Since you're going to have your converter on all the time (while on shore power) I would absolutely get one with the right charge profile, but not until you have the LiFePO4 battery or batteries installed.
4. The typical inverter/charger that most of us are putting in our RV's would not understand that you want to use solar first and then shore power.
5. The components most likely need to be indoors, not exposed to the elements. But you can create a system that doesn't fully integrate with the RV. Look for threads started by forum member @Firetodd . He just completed an install like this.

Better to ask the "dumb" questions now, rather than later after you've started buying stuff or you've installed it and it doesn't work.
thank you for answering my questions, i really appreciate it. it helps a lot and gets me going in the right direction.
 
We are first time RV owners who knew nothing about them when we purchased 2 years ago but our RV did come with solar which we love but in reality unless you have a very big system and put in a lot of bucks on a big battery bank you are likely going to not meet your power needs on a fulltime bases. We are fine a few days at a time but doing so with no ac.

Additionally living in Texas I understand all about heat, humidity, and the loud RV ac. A mini-split sounds nice but you will likely run into some major issues with fighting humidity as the mini-split is not going to be very good on that front. There are some high end RV ac that are more efficient and if you look on YouTube for Travelling Robert he has a new RV that runs the ac via his solar set up. Not sure how long he can run it but it is a more efficient ac. His set up will give you a good idea of what you might need.
 
@fabiangomez Here is a link to my solar build that I installed on my fifth wheel: https://diysolarforum.com/threads/solar-panel-mounting-on-rv.22683/

I wanted a system that I could easily remove if needed and would allow me to power the entire electrical system without drastically changing the wiring of the camper. I used a MPP LV 6548, 10 350 watt solar panels, and built my 48V battery with 16 280ah 3.2v cells and BMS. That link details my build. The fine folks in this forum were invaluable in assisting me!
 
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