Skip to main content ↑ ↓
Topic: Solar experiment (Read 2093 times) previous topic - next topic

Re: Solar experiment

Reply #25 –
Quote from: Pierce & Gaylie Stewart –
Lots of great panels from China. They are absolutely on top of the latest developments. More vibration and abuse-resistant? Come on, I installed our Chinese panels many years ago and through many branches and small trees, they don't have a mark on them. Solar farms would not use hundreds of thousands of them in the U.S.  if they were poor quality.

Our 1140 watt potential is more than enough for our coach. It runs everything including a 50 inch 4K TV and microwave without ever starting the generator and even uses the OEM inverter. The AGM batteries came from a bankrupt solar company and 4kWh only cost $210 for all six. They work fine today.

Throwing megabucks at it sort of defeats the purpose and is a lot more than many of us have budgeted for.

My view!

PIerce

Must be two volt. What make and model and most important weight? Jim 
                edit: bad math, 6 or 12 volt batteries?


Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Solar experiment

Reply #26 –
I agree with Pierce, with a serious energy use audit 1200 watts is plenty for us. You need enough battery capacity to get by for 16 hrs in the winter at cold temps, that was our goal there. A week in reasonable conditions is pretty easy for us but then we are careful with power use.  There are lots of great panels out there.  Twice the price doesn't mean you system is better, just more expensive.  Lithium batteries would be nice it they were like a Tesla Wall, built in temperature management, still a lot of money but if you used micro inverters, solar directly to 220V to charge it and its internal systems back to your coach at 220v/120v with a modest sized 12v battery bank for internal 12 v ... something else to think about.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Solar experiment

Reply #27 –
Well, the experiment continues. Last weekend I went to the coach and checked the start battery right out of the chute. 12.3 v. About 70%. We had had about 3 days of strong sun, the rest partly cloudy. Started the coach and let it run for about 15 minutes. Didn't have time to take it for a spin. Today, did the same. the battery reads 12.2 v. About 60%. We have had mostly cloudy conditions this past week, with only intermittent sunshine. Not bad, but not conclusive. I will continue to monitor the batteries for several more weeks. If it seems like they get much lower than 12.2, I will pull the batteries and bring them home to trickle charge on the shelf. One other note, I forgot and left the salesman switch on this past week. I hope that contributed to the added decrease in battery voltage.

Larry
Larry Warren
1996  U320 36' SBID "Lola" sold 2020
Build #4970
Motorcade #18318

Re: Solar experiment

Reply #28 –
Our coaches use "false 220V", or two 120VAC legs of the same phase. 220 V microinverters would work, but a 120 V inverter would work fine.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: Solar experiment

Reply #29 –
Tim time to proofread what you said, as It may confuse many, and generator or a 20 or 30 amp circuit and are strickly 120 volt. So I don't understand your point about a 220 volt inverter.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Solar experiment

Reply #30 –
Agreed. Our generators make only 120 VAC, which the transfer switch applies to two separate 120 VAC legs in our rigs as follows:

1. Low power legs
120 VAC part of the propane-electric fridge, battery charger (battery feeds lights and 12 volt propane appliances like water heater, furnace and air conditioner controls), 120 VAC outlets and ice maker.

2. High-power legs
Air conditioner(s) and engine pre-heater.

My point is that the 220 VAC solar microinverters, meant for grid-tied applications, should work fine given some smart engineering design modifications. For example:

1. May need a 220 VAC battery charger and a new transfer switch to recognize the presence of 220 VAC from the solar microinverters and apply it to the battery charger.

2. May need to throttle AC (Alternating Current) power demand from the battery charger.

3. While running on solar power only, may need to run a separate inverter to power the 115 VAC systems.

Sounding complicated yet? It may be!
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: Solar experiment

Reply #31 –
Larry,
The salesman switch ordinarily doesn't have any connection to the chassis battery bank unless the boost switch is on... but it has been awhile since I read the earlier posts in this thread so maybe you factored that in already.
Don
Quote from: ohsonew –
...One other note, I forgot and left the salesman switch on this past week. I hope that contributed to the added decrease in battery voltage.

Larry
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Solar experiment

Reply #32 –
Tim can you tell me if and how my magnum pt-100 solar controller would interface with my coach?
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Solar experiment

Reply #33 –
After checking the batteries today, I have decided to pull them and bring them to a warm garage with a trickle charger. It has been cold (down to 10 one morning), snowing ( 3"), and cloudy for a lot of the past 2 weeks. When I checked the batteries today, 12.1 v. about 55%. I know that we have a lot of winter left, so I am not going to chance ruining brand new batteries. If I could tilt the panels &/or be able to go and clean off snow etc. I might be more comfortable with leaving them on solar. Since the sun is so much lower in the sky and my work schedule won't allow me the time to monitor closer, it's time to take preventative measures. Perhaps I will test again when the sun is getting higher in the sky.

Conclusion, not unsuccesful, but not as good of results as I had hoped for.

Larry
Larry Warren
1996  U320 36' SBID "Lola" sold 2020
Build #4970
Motorcade #18318

Re: Solar experiment

Reply #34 –
I have had best results if I start with new batteries  fully charged and be paranoid about letting them ever be discharged and not recharged.  Hence the auto connect relay versus a isolator and enough solar to recharge both banks in storage.

I do not have enough solar for recharge from use quickly.

Once ruined they are not fixable readily. 

Foretravel equipped the unicoaches new with AGM redtops for the engine and house gels that are harder to damage from discharging and do not require and will not accept equalization.

Option is lifeline agm's with 10% more capacity that if run down may be equalized and capacity restored.

All others other than flooded cell are not restorable once sulphated.  Maybe the high frequency add on can restore batteries and I am told they do work.  Takes months but does work
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Solar experiment

Reply #35 –
If a battery(s) is fully charged, it won't freeze and will keep it's charge all winter. But you have to disconnect the bank from the coach or the parasitic drain will flatten and ruin them.

Pierce
Pierce and Gaylie Stewart
'93 U300/36 WTBI
Detroit 6V-92TA Jake
1140 watts on the roof
SBFD (ret)

Re: Solar experiment

Reply #36 –
Take a look at the tech specs before buying solar panels.

Sunpower panels have far less efficiency loss in terms of temperature coefficient and long-term loss parameters.

The Chinese sometimes stretch the truth about their panels, or hide the truth.
1997 U270 34FT Build 5140 Cummins 8.3 Allison 3060R
Solar 1920Watts, 14KWH lithium. Orion BMS.

Re: Solar experiment

Reply #37 –
Sent my guru buddy the sun power panel info and my pt100 controller info.

No idea if and how they may work together.

I have a family member in the solar biz.  Maybe he can source the panels when I am ready.

Would be interesting to be self contained without running the gen....

I have a matching gen start box and the advanced controller for the inverter.  And i understand it works with the solar controller

Tesla says they back burnered the powerwall to concentrate on their model 3 cars ramp up
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4
 

Re: Solar experiment

Reply #38 –
Code changes coming and potential liability issues with Current generation product are also affecting powerwall strategy.
Code changes to require potentially two hour fire rated room for powerwall driving up install cost Tesla model 3 now 4-6 weeks delivery, Tesla on pretty shaky financial footing. Will be interesting to see what future holds for Tesla. Great innovation, I am rooting for them

Tim Fiedler
Gen-Pro.biz
630 240-9139
Tim Fiedler    2025 LTV Unity MBL on Order
2000 Chevy Tracker 2 Door Convertible 4WD Now lifted 4.5"
1985 Citroen 2CV6 Charleston
Murphy Rebel on wheels with 175HP Titan
Cessna P337
1980 48' Westport MY (!/4 Share)