Skip to main content ↑ ↓
Topic: Reimagining Solar With Heat & AC (Read 1965 times) previous topic - next topic

Re: Reimagining Solar With Heat & AC

Reply #25 –
Mike I sure am grateful for all the work you and others have done towards perfecting these battery and solar systems hopefully all the bugs will be worked out in a couple years when I'm ready to upgrade. Next generation batteries should be out by then too
Scott

Re: Reimagining Solar With Heat & AC

Reply #26 –
Thanks,  I also found a source of used LIpo batts.   
 My old friend races EV cars and has some that are out of his very specific parameters, but well within what we can use. 
  He picked 4 cells  at 3.82V, bottom  balanced,  and assembled a 12 V set for me to run and test.   
 185 AH .  About  400$ .   

Re: Reimagining Solar With Heat & AC

Reply #27 –
Quote from: Protech Racing –
Thanks,  I also found a source of used LIpo batts.   
 My old friend races EV cars and has some that are out of his very specific parameters, but well within what we can use. 
  He picked 4 cells  at 3.82V, bottom  balanced,  and assembled a 12 V set for me to run and test.   
 185 AH .  About  400$ .   
I never would of thought of race take off batteries. That is great idea. I'm currently trying to get my hands on 5 or 6 race take off tires for the prerunner. They won't run and I could never drive hard enough to destroy. Now if I can track down a set of batteries in a couple of years. Everyone is a winner

Re: Reimagining Solar With Heat & AC

Reply #28 –
You guys are killing me!!🤣🤣
Richard & Betty Bark & Keiko our Golden Doodle
2003 U320T 3820 PBDS
Build # 6215
MC # 16926
2016 Chevrolet Colorado 4X4 diesel

Re: Reimagining Solar With Heat & AC

Reply #30 –
 There may be more of these cells  for sale , If they work as described.  How much is one set worth?

Re: Reimagining Solar With Heat & AC

Reply #31 –
The AC is running in ECO mode  at 4 amps -119 volts .  It wont quite run  full mode unless the engine is running the GM extra alternator .
So using about 41 @ 12 volt amps.  Working well but could use more roof watts.
 91 outside. 83 inside
 Roof is putting out 752 on one set and 730 on the older set of 3 panels.
At or over the rating for each.  Almost 55?amps in full sun.
Very happy so far.

Re: Reimagining Solar With Heat & AC

Reply #32 –
Today I added a deep cycle LA battery  for back up.  After the LI Po  battery pack went to 9 volts and  the solar chargers wouldnt charge it  , leaving the generator also dead. I want to make sure that I'm not dead in the water if the LIPO goes flat again.
  I know that I can start the engine and run the boost to recover but I like better odds.
 The battery is Auto Zone Deep cycle 29DP-DL    About 100$   

Re: Reimagining Solar With Heat & AC

Reply #33 –
Shouldn't your BMS or inverter have a cutoff set higher than 9 volts?
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Reimagining Solar With Heat & AC

Reply #34 –
 Both inverters shut off at 11.8.  Not sure what actually happened to kill the batts.
 No BMS  .
These are a 400$. 180 AH set

Re: Reimagining Solar With Heat & AC

Reply #35 –
LiPo batteries voltage will drop scary fast when they reach depletion, IOW from 11.8 to 9 volts is much less capacity than you would imagine. Any other items using 12 volts could have caused this drop, water pump, lights, heater, fridge (if on dc or propane), water heater.
Hopefully your LiPo cells weren't damaged. A good BMS would have prevented this.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Reimagining Solar With Heat & AC

Reply #36 –
 I replaced 2 of the 240 watt with 2- 410 watt Trina panels .  Now I have 4 240 watt into one controller, and 2 410 into the other controller .  Each set puts out around  30 amps to the battery and that is  about  enough to run the AC at 8 Amps.
  If it gets cloudy at all the balance goes to the AC and the voltage drops to  the cutoff of 11.7 .
  So summery ; The 12000BTU Pioneer Minisplit uses about 8-9 amps @ 120 Volts, at full boil. 
 I have about a total of  60-70  plus 12 volt amps charging the batteries.
 In full sun at 88* the bus will stay at 77* easy with the batts staying over 12.5 volts.
 My original estimate  regarding 200% watts of solar for the watt required by the AC  is pretty valid .
  My  theoretical solar watts    is near 940 on one system and 820 on the other. 
      The AC uses about 1000 watts  in run and 650 ish in ECO mode .
 
      This continues the bad at math engineering ;  350$ for the 4 240 watt panels .  $400 For the 410 panels. $250 for controllers. 100 cables etc.  800$ for the minisplit ,    400$ for the 2 inverters.
            The gain is no gen for 90% of the parked time and all of the road time .  The package runs the engine fans, resi fridge, a couple of inverter  outlets  .  The actual ROI at 4$ PG propane is about 600hrs.    Plus the headache of filling the tank and the noise .
  I also have some race car math  that may have some flaws.  Maybe ..

Re: Reimagining Solar With Heat & AC

Reply #37 –
Latest .  Fired up the  solar/ AC,.  Amp output was very low .    My bus sits outside still and has collected a fair amount of pollen on the panels.    Not really  noticeable, but some dust.  Mopped the panels and almost doubled the output .  I also reduced the number of connections  in the solar systems  and picked up a few more amps . 
 So now I buy a bag of connectors and a roll of of 10 wire . Solder  about everything .
  I recommend buying only the 410 watt or higher used or new  for rooftop mounting.