mjsandiego2003
New Member
- Joined
- Feb 26, 2021
- Messages
- 6
Hi all,
First post here, and I'm hoping you all can give me solid advice. I am trying to maximize the solar charging and battery storage on my 2020 Thor Magnitude RV. I have no background in PV system design, but I do my research and hope my first attempt isn't too full of issues. I'm a relatively experienced engineer, but not with PV, or any significant electrical systems.
My coach is somewhat unique in that it has a residential refrigerator inside, and a mini-fridge outside, both of which are electric only. With the two 6V batteries I currently have, I am not able to even make it through the night while boondocking in the desert. And we boondock... alot. Like 10-16 weeks a year. I do not need to run AC, or go bigger than the current 2k inverter inverter I have (It covers the fridges, TV, fans and a few 110 outlets in the coach), really just trying to keep the batteries charged without running the generator 8-10 hours a day while boondocking. Oh, and without completely braking the bank.
My main constraint s I really do not want to put more holes in my roof. and my wife Reeeeaaaaaalllly doesn't want them either, and as they say, Happy wife, Happy Life. My second constraint is space, I cannot afford to give up a storage bay for solar, and the electrical system is literally right under the dinette (Plus they are insulated)
Fortunately my coach is "pre-wired" from the factory for solar, only problem is its with 10awg wire. So my thought are...crank up the voltage. I can physically fit at least 8 Renogy 175W Flexible panels on my TPO roof. My initial calculations (compensating for temperatures, and giving 25% margin) for those panels with 4 panels in series, and 2 parallel series has 1400W, Voc @ ~104.43V and ~23.75Amax. Assuming those numbers are close, I have some questions are my questions:
First post here, and I'm hoping you all can give me solid advice. I am trying to maximize the solar charging and battery storage on my 2020 Thor Magnitude RV. I have no background in PV system design, but I do my research and hope my first attempt isn't too full of issues. I'm a relatively experienced engineer, but not with PV, or any significant electrical systems.
My coach is somewhat unique in that it has a residential refrigerator inside, and a mini-fridge outside, both of which are electric only. With the two 6V batteries I currently have, I am not able to even make it through the night while boondocking in the desert. And we boondock... alot. Like 10-16 weeks a year. I do not need to run AC, or go bigger than the current 2k inverter inverter I have (It covers the fridges, TV, fans and a few 110 outlets in the coach), really just trying to keep the batteries charged without running the generator 8-10 hours a day while boondocking. Oh, and without completely braking the bank.
My main constraint s I really do not want to put more holes in my roof. and my wife Reeeeaaaaaalllly doesn't want them either, and as they say, Happy wife, Happy Life. My second constraint is space, I cannot afford to give up a storage bay for solar, and the electrical system is literally right under the dinette (Plus they are insulated)
Fortunately my coach is "pre-wired" from the factory for solar, only problem is its with 10awg wire. So my thought are...crank up the voltage. I can physically fit at least 8 Renogy 175W Flexible panels on my TPO roof. My initial calculations (compensating for temperatures, and giving 25% margin) for those panels with 4 panels in series, and 2 parallel series has 1400W, Voc @ ~104.43V and ~23.75Amax. Assuming those numbers are close, I have some questions are my questions:
- Is that safe/appropriate to be running those numbers through ~25ft of 10awg wire?
- If the problem is too high a voltage, I can knock the series down to 3 in series, I get 1050W and Voc 78.32 which is better than nothing.
- If the problem is current, what's the max current I should run?
- I plan on using flexible panels, glued to the roof (maybe using corrugated plastic underneath for some insulation). I know rigid panels that tilt are ideal, but remember the holes in the roof issue. So I know I am going to face some inefficiencies due to angle, and heat. Is it ok to use a 60A Renogy Rover MPPT and just cap the output power at 800W? None ever gets listed wattage in rea-lworld output, I figure If I can get a solid 800W I should be fine. Price is attractive as well as size, which is the bigger issue. Again, I am not looking for the most efficient system, but I do want it to be reliable.
- What else am I missing? Below is the current plan. I'm looking to start purchasing parts, and have a parts list, but the main components that may not be recognizable are:
- Renogy 30ADC-DC converter (I like this not only for alternator charging, but picking up a few "briefcase" type panels if I have need more charging)
- Renogy Rover 60A MPPT (Inexpensive, only reason Its on my list, if this is a bad idea, I'll upgrade to a higher amperage)
- Victron Lynx (I imagine i could just use a busbar, but it seems like all the cool systems have this)
- WFCO WF-9855-LiS (This converter is plug-and-play in my coach)
- Battlborne GC2 (no brand loyalty here, I am also interested in the SOK. I originally thought about these because they will fit in the stock battery tray, but I decided against putting them there due to cold exposure.)