Please help. Building My First System!

[Pneuma]

Hello everyone.
I am moving from Ny to Texas. going off the grid( No access what so ever to grid). I have been trying to educate myself on the Solar power topic as much as possible. The moving day is getting closer and so I have to get the spesification of my system down so I can just buy everything and hopefully they all work together.

I wanted to post my system here and ask you nice people to take a look at it and help me out please.

For my batteries I decited on a 24V:

Grade A NEW 16PCS 3.2V176Ah Lithium Iron Phosphate Cell lifepo4 battery solar 24V​

I am planning on Parallel two 24v 176AH to create a 24V with 352AH. I believe thats how you write it 8s2p

For the inverter and charge controller I think Im better off going with all in one.

Growatt 24V SPF 3000TL LVM – 3kW 120Vac Stackable Inverter 2kW MPPT Charge Controller Split Phase 120V/240V capable with two or more units​

Or something similar. I really could use some help in this.

for solar pannels... I havent really decited on what brand or exactly what I am going to buy. I would love to get LG or Sunpower but also Rish Solar has been sitting well with me.

regardless of the brand I am thinking about 1150Watt( 3x350) To START WITH because I am kind of on a budget right now and decited to spend the majority of the money on the battery. and Also I have a limmited roof space on my to be RV.



I am planning on powering a Desktop a laptop a fridge and in hotter months obviously AC since you know Texas ... An instant watter heater bunch of lights and a vacuume once in a while.

I am not planing on runing anything 24/7 except for the fridge and I know I need to adjust my use. Thats going to be fun going from 875Kwatt a mounth !

Any comment is widley appreaciated!

Thank you for reading my post

 

[Hedges]

Fridge ... RV ... running 24/7

Is the fridge propane/electric absorption cycle? If so, power hog, replace with one that uses a compressor, either DC or 120VAC.

Don't run 24/7. Run while the sun shines, and let ice in freezer keep it cold through the night.
Bottles filled with brine (tuned for your target temperature) should keep freezer at desired temperature below 32F

 

[Pneuma]

Yeah I had no idea. I do not own a fridge yet so when buying I am MOST DEFFINITELY going to remember your advice Hedges Thank you so much for that comment. <3

 

[Hedges]

"instant watter heater"

tank-type instead, heat it with surplus power when battery full.

 

[HRTKD]

How big is the RV? How well insulated? Four season? How many A/C units on it?

Without knowing the A/C draw, I suspect your current specs won't run the A/C for long. If you had more solar to cover both the A/C and battery charging during the day, it's more likely.

For boondocking, I run a propane refrigerator in my trailer. I can run the refrigerator a long time on propane.

 

[Pneuma]

The RV is 7x24 and only 1 Air Conditioner I believe its draw is between 500 to 1000 Watt. the good thing is, winter is coming and I wont be needing to run it anytime soon, giving me time to add some Panels in the future.

 

[Hedges]

To start the AC probably requires inverter rating (or surge rating at least seconds not 30 milliseconds) 5x nameplate.
Panels flat on the roof of course will produce less than PTC ratings unless sun is directly overhead. But good news is 1000W is only 3 or 4 panels and about $400.

 

[Pneuma]

With the dimentions I have to work with I am trying to get higher watta panels I stillk have to look into the dimentions of the panels and how big they are to see if I even can fit them all on my Roof.

I should Also mention that this is a trailer not an RV it is going to be stationed and not move Sorry for the miss information it got lost in the translation.


Ok so

LG NeONR LG-350Q1C-A5 350 Watt Mono Black Frame Solar Panel​

Dimention is

66.93 × 40 × 1.57 in So I should alright... I think.

 

[HRTKD]

Don't forget to take into account the mounting brackets. They add about 1.5" on each side. Unless you're using something like Unistrut you cannot mount panels next to each other with no space in between.

My 320w solar panels are very similarly sized. I ran them parallel to the length of the trailer. I have a popup vent between them (barely). My trailer is full width, about 96" I believe. It's a tight fit.

 

[Pneuma]

That’s awesome! Yeah I should be ok with the panels. I really do not want to do ground mount but I hardly think I’m going to need to.

One question though with me using the all in one inverter/controller, am I going to need to add fuses or anything extra or can I just connect the batteries directly to the unit?

 

[HRTKD]

You should still put a fuse between the battery and the load.

I don't know much about the All-in-one component. I don't use one. Here is how my system is connected.
Common Positive Bus Bar -> Switch -> Fuse -> Battery +
Common Negative Bus Bar -> Shunt -> BMS -> Battery -

I think you would connect your All-in-one to the common bus bars.

 

[MichaelK]

If you haven't selected panels yet, look first on Craigslist rather than purchasing retail. Shipping is built into the price, if it isn't added later, and you'll get far better deals on local pickup rather than mail-order. Here's what I found in a quick 10-second search...

260 WATT REC PEAK ENERGY Z-LINK SERIES REC260PE Z-LINK SERIES USED -...

WE DO NOT SHIP, BUYERS PICK UP ONLY, WE WILL LOAD ONTO AT NO ADDITIONAL COST. ***PURCHASED FROM...

sanantonio.craigslist.org

I bought exactly these same panels from a completely different local seller, and I am very happy with their performance.

If you are expecting your AC to use 1000W, then my recommendation is to have at least 2000W of panels. That's because 1000W of panels facing south will NOT be producing 1000W at 5pm when the sun is far to the west. You want AC at 5pm, right?

I know you want to put your panels on the roof only, but the positioning of the panels on the ground, gives you the opportunity to use rotating mounts, like the one I'm showing here. For the 1000W array I have in the pic, I was producing 920W at 4:00pm with the array rotated west. BTW, I only paid 220$ total for those four panels off of Craigslist. The frame steel cost more then the panels themselves!

In terms of fusing, I'm using this kind of combiner box, that utilizes DC breakers.

MidNite Solar MNPV6 Combiner Box - RES Supply

Free Shipping! MidNite Solar MNPV6 Combiner Box, 120A for 6 PV Breakers or 4 Fuses

ressupply.com

I also recommend using a power center like this...

Schneider Electric 865-1016 Conext SW DC Breaker Panel - RES Supply

Free Shipping! Schneider Electric 865-1016 Conext SW DC Breaker Panel, Includes 250A Breaker, RNW8651016

ressupply.com

Note though that power centers are brand specific, but functionally identical. Pay attention though to each companies wiring diagrams, because they may add a ground-fault breaker, or other component to an individual panel/inverter combination to keep them 100% code complainant.

 

[Pneuma]

You should still put a fuse between the battery and the load.

I don't know much about the All-in-one component. I don't use one. Here is how my system is connected.
Common Positive Bus Bar -> Switch -> Fuse -> Battery +
Common Negative Bus Bar -> Shunt -> BMS -> Battery -

I think you would connect your All-in-one to the common bus bars.

Thank you for that. It really helped me with the whole fuse topic. Also Im now thinking about replacing the One In All It just seems that I would be having so much more control and If I wanted to upgrade in the futre I guess it would be easier.

 

[Pneuma]

If you haven't selected panels yet, look first on Craigslist rather than purchasing retail. Shipping is built into the price, if it isn't added later, and you'll get far better deals on local pickup rather than mail-order. Here's what I found in a quick 10-second search...

260 WATT REC PEAK ENERGY Z-LINK SERIES REC260PE Z-LINK SERIES USED -...

WE DO NOT SHIP, BUYERS PICK UP ONLY, WE WILL LOAD ONTO AT NO ADDITIONAL COST. ***PURCHASED FROM...

sanantonio.craigslist.org

I bought exactly these same panels from a completely different local seller, and I am very happy with their performance.

If you are expecting your AC to use 1000W, then my recommendation is to have at least 2000W of panels. That's because 1000W of panels facing south will NOT be producing 1000W at 5pm when the sun is far to the west. You want AC at 5pm, right?

I know you want to put your panels on the roof only, but the positioning of the panels on the ground, gives you the opportunity to use rotating mounts, like the one I'm showing here. For the 1000W array I have in the pic, I was producing 920W at 4:00pm with the array rotated west. BTW, I only paid 220$ total for those four panels off of Craigslist. The frame steel cost more then the panels themselves!

In terms of fusing, I'm using this kind of combiner box, that utilizes DC breakers.

MidNite Solar MNPV6 Combiner Box - RES Supply

Free Shipping! MidNite Solar MNPV6 Combiner Box, 120A for 6 PV Breakers or 4 Fuses

ressupply.com

I also recommend using a power center like this...

Schneider Electric 865-1016 Conext SW DC Breaker Panel - RES Supply

Free Shipping! Schneider Electric 865-1016 Conext SW DC Breaker Panel, Includes 250A Breaker, RNW8651016

ressupply.com

Note though that power centers are brand specific, but functionally identical. Pay attention though to each companies wiring diagrams, because they may add a ground-fault breaker, or other component to an individual panel/inverter combination to keep them 100% code complainant.

No i have not selected my panels yet and I am so glad that I am seeing your post before I did. That sounds awesome Thank you!

I like the concept of being about to rotate the panels however I am not sure how well that is going to work out since where I'll be moving to has high winds But I am so digging how your solar panels look with that ground munting thats So NEAT!. Congrats!

I honestly Am not familiar yet with combiner boxes I am looking them up as writing this...

The whole solar Topic is a very intersting and I definitely have much passion for it but this is my first time so I feel like there are a lot to concider specially because I really want it to be safe. I'm just hoping that all of this can come together in my brain and I can execute them succesfully!

 

[Pneuma]

I am also wondering that If I need to use 2 BMS for that battery configuration?

 

[Pneuma]

I am also wondering that If I need to use 2 BMS for that battery configuration?

I just figured out that instead of putting 8 of them in series and then putting them in parallel I need to Parallel them first then just series them all togehter so I can just use a 8s BMS.

Also I am seeing that with a BMS I am going to be limited to about 100ah discharge so I'm guessing I am going to have to use a Battery protect?

 

[HRTKD]

Thank you for that. It really helped me with the whole fuse topic. Also Im now thinking about replacing the One In All It just seems that I would be having so much more control and If I wanted to upgrade in the futre I guess it would be easier.

It all depends on how confident you are at designing your own system. An all-in-one is attractive as it's all there, which greatly simplifies your design, purchase and installation.

 

[dirtybobby423]

It all depends on how confident you are at designing your own system. An all-in-one is attractive as it's all there, which greatly simplifies your design, purchase and installation.

You can also add additional all in one units for increased capacity which is nice.

 

[DASH]

Roughly speaking the configuration You mentioned above, in the summer, will on average, give You enough power to run the A/C (with the compressor continuously running) for about 5 hours (if no other electrical appliances are used) a day, providing You have the solar cells in a optimum orientation. There are charts, and formulas available that can give You a more exacting figure.

 

[digit]

didnt see a specific mention of air conditioner type but i highly recommend a mini-split w a seer rating over 20
looks like youre on the right track