massive solar install

[Mako_Kupo]

hey everyone! it was a cold winter, but I made it through with minimal issues. my yeti lithium 1400 + 550w 12v renogy panels more than covered what I needed through the season. however, it is now time for my permanent install. I did a TON of research and reading over the winter, and I still remember most of it but some stuff wasn't super clear to me.

to start, this will be my basic specs. currently 550w 12v renogy solar panels, upping to 800w in near future. 800w is where it will cap out for this motorhome, unless I want to start covering the sides of it with panels. I bought the tp of the line converter over the summer, but found someone who desperately, desperately(yes, two desperatelys) needed it. I have them a deal on it, since I was more than taken care of power-wise. I am very much a pay it forward person, and help people whenever I can.


that said, I need to know what I need. I have my panels, with the wires coming through the roof cleanly, so that is all done for now. i need a minimum of 600AH(12v) lithium, and the charge controller/equipment to support that. so, moving forward, know that I only have panels for my final build. I need everything else.

I was thinking battle born lithium batteries. they use cylindrical 26650 cells, with a good warranty. price is about $1,000 per 100ah. if you get six of the batteries, its $6,000 but you get the charge controller, inverter, battery monitor, and inverter. there is all sorts of safety built into the batteries. I consider building my own battery bank from lithium cells, but decided I want to live:B.

I would get this

https://www.amazon.com/Battle-Born-Batteries-Journey-Lithium/dp/B07CTYZ38J/ref=sr_1_5?ie=UTF8&qid=1530450271&sr=8-5&keywords=Battle+Born+Batteries

and this

https://www.amazon.com/Progressive-Dynamics-PD4590-Inteli-Power-Distribution/dp/B002OR41YS/ref=sr_1_2?ie=UTF8&qid=1530450380&sr=8-2&keywords=progressive+dynamics+50+amp

I'm hoping thats everything I would need. I already have 6x 120v circuits installed under my insulation, and 12x 12v circuits. its a ton of circuits. my dad taught me - if you have room to dedicate breakers, do it(basically).

will all of these things work together? I think the inverter the battery bank comes with will be not used, right? the PD converter does everything from taking a charge from the solar controller, taking a charge from the alternator, powering both 12v and 120v, and can charge batteries via shore power. there are a lot of parts here, and I just want to make sure I'm not building a fire pit, but a camper instead.

[Almot]

dave17352 wrote:
I would think they are selling what they think are appropriate

I looked into Battleborn a while ago, they don't make chargers. On their site they sell Progressive Dynamics PD9100L series, namely 30-60-80A.

Manual. No charging profile that I can see, though 3 pages of safety instructions :).

[2oldman]

Mako Kupo wrote:
I know its an inverter and will invert 12v to 120v, but I can't figure out what else it does. int allows me to plug into shore power and charge my battery bank. if thats the case, I don't need the conventional RV converter setup right?

No, the charger in the Aims will not likely work for Li batteries. Li's don't require 3-stage charging, most just do bulk and float.

Those panels you listed must be connected in parallel. In series you'll lose a lot of amperage with those small panels.

[pianotuna]

Hi,

I don't recommend AIMS. There is no easy way to use a 24 volt inverter with a 12 volt battery bank.

Since the panels are nominally 12 volt, but different amperages, the battery bank has to follow suit at 12 volts.

It is unlikely that I would have purchased the panels from renogy and unlikely that I would have gone with 12 volt panels at all.

[Mako_Kupo]

pianotuna wrote:
Mako,

In your shoes parallel may be the best you can do. That, of course, means sticking with 12 volts. Or sell the panels and start over.

thats okay with me. I bought my panels to fit my roof perfectly, once I have the rest up there ill upload pics. I do have a youtube channel(Rollin Nerdy) if you want to check it out.

what I can do is buy compatible 24v stuff that will also work with a 12v setup, so eventually I can build a 24v system and all ill need is new panels. not a major loss, as least I don't think so. it just means fat cables (which I already have), and it means I get to work with what I am familiar with. I do love learning new things and will eventually switch to 24 or 48v.

so for 12v, do you recommend the things I linked in the OP?

https://www.amazon.com/dp/B00NLLSGMY/ref=twister_B00XKDUM9I?_encoding=UTF8&psc=1

I know its an inverter and will invert 12v to 120v, but I can't figure out what else it does. int allows me to plug into shore power and charge my battery bank. if thats the case, I don't need the conventional RV converter setup right? thank you so, so much!

side note: this is a wonderful idea I think. picture you moving into a 20 foot motorhome that already has permanently mounted 850w 12v solar panels all in parallel. you have $8,000 to spend on your power supply. a generator is not an option. knowing what you know, and what you have for panels, what would YOU guys buy? lithium is a must.

[pianotuna]

Mako,

In your shoes parallel may be the best you can do. That, of course, means sticking with 12 volts. Or sell the panels and start over.

[Mako_Kupo]

pianotuna wrote:
Mako Kupo,

The only additional cost of using 24 or 48 volts is adding a dc (48 v) to dc (12 v) converter capable of running the minor 12 volt loads in an RV.

A few benefits are smaller wiring, an inverter that doesn't have to work so hard and no worries about balancing parallel batteries.

The disadvantages (it is always a trade off) are that each cell has to produce all the watts needed. That may cause them to exhibit greater voltage drop. If this is a problem at 48 volts, then going to 24 may be worth consideration.

However this is all moot as you now have invested in a 12 volt inverter capable of running your RV to your needs level.

I think LI jars are wonderful. It is just the cold that keeps me from them.

May I ask you to list the equipment you chose for the RV?

I missed this, sorry. I have not yet purchased the 12v inverter, it is all just on a list. I have the budget, am just trying to put together the setup I need. I would love to build a good list on here. I posted the panels I have above, aside from that I have literally nothing. the panels are hooked up tot a yeti lithium 1400, providing power to everything in the rv.

[Mako_Kupo]

pianotuna wrote:
The advantage of panels in series is an earlier start to the charging day, a later end to charging day, and more likelihood of power generation when there are poor or cloudy conditions.

My system maxes out at 17 amps @ 12v output (nominal) and even in rain I get 4 amps at solar noon. My own system is series/parallel with a nominal input voltage of 33.

interesting. currently in heavy rain the max I've produced is 22w, didn't check the amps.

I knew a few of the 24v/48v benefits as in efficiency, thinner cables(id keep the same old fat cable why not) but thats about it.

so I have
1x renogy 12v 150w mono panel
1x mighty max 12v 150w mono panel
5x 100w renogy 12v mono panels
3x 50w 12v renogy mono panels

because of the odd numbers I can't do a perfect 24 or 48v setup with what I have correct? best case is leaving out 1x 100w, and 1x 50w panel. right? thanks!

[pianotuna]

The advantage of panels in series is an earlier start to the charging day, a later end to charging day, and more likelihood of power generation when there are poor or cloudy conditions.

My system maxes out at 17 amps @ 12v output (nominal) and even in rain I get 4 amps at solar noon. My own system is series/parallel with a nominal input voltage of 33.

[Itinerant1]

Pianotuna with all my surfing/ lurking I do on rv forums they haven't made a showing yet or at least that I've seen.
Only place that I've read is on the boat forums. Or bloggers with boats. They do look like a good trade off though when Lifepo4 won't cut the cold environment you have to deal with.

[pianotuna]

Mako Kupo,

The only additional cost of using 24 or 48 volts is adding a dc (48 v) to dc (12 v) converter capable of running the minor 12 volt loads in an RV.

A few benefits are smaller wiring, an inverter that doesn't have to work so hard and no worries about balancing parallel batteries.

The disadvantages (it is always a trade off) are that each cell has to produce all the watts needed. That may cause them to exhibit greater voltage drop. If this is a problem at 48 volts, then going to 24 may be worth consideration.

However this is all moot as you now have invested in a 12 volt inverter capable of running your RV to your needs level.

I think LI jars are wonderful. It is just the cold that keeps me from them.

May I ask you to list the equipment you chose for the RV?

[pianotuna]

Itinerant1,

Any mention of Firefly batteries on the airforums? LI just won't do for me due to cold weather limitations.

I'm starting my 3rd summer with used telecom jars and so far they are holding up extremely well. Cost was below $1 per amp-hour, including tax. I push them hard--176 amps of load from the microwave.

[Itinerant1]

Also if you haven't claimed the 30% tax credit claim it, $1800 off of $6000 doesn't hurt.

[Itinerant1]

Mako Kupo if you haven't been to airforums.com (airstream trailers) then the electrical sub forum there is alot of info/ threads there for Battleborn batteries.

Yes Lifepo4 cost more upfront but the benifits out weigh the dead lead.

[Mako_Kupo]

2oldman wrote:

pianotuna wrote:
I don't see 800 watts of solar as massive.

I have 835w which I also do not consider massive. I consider it adequate.

Massive is when you cover your roof, hang them over the side and have a utility trailer full.

apologies, I only live in a 20 foot motorhome, so I thought 850w was pretty beastly especially combined with a huge lithium bank. I thought it'd be 800, but I was able to get 850 up there. I have my new panels on the way.

(second quote, can't figure out how to do two at once)I personally wouldn't spend the money in Lith Batts. Ive used Trojan T-125's now for 14 years. They also make larger batts specifically designed for deep cycles heavy industrial use. Yes they weigh more but they work great. I have 428 watts on my TT. We will be moving to a fiver soon and I will put 6-800 watts up top, but will increase to 4 batteries, or two with greater capacity and a MPPT controller.

the reason I don't want to go with agm, sealed, gel, or others are the lifespan. lithium costs more up front, but is cheaper in the long run and I am just getting started.

I went very basic with the install, all parallel panels. I still do not really know how panels in a series works, all I know is its hooked up differently and can provide higher voltage which is always nice. wouldn't it be significantly more expensive to do everything in 24v? also weight is a huge issue, I work online and keep what is ell int he camper with me. I on average am hauling an additional 2,000 pounds on top of the camper weight. I don't think it could handle the weight of 6 agm's on top of everything else, not to mention I don't have the room for them. lithium is really the only option.

thank you everyone so far!