Solar Panels - Fixed Vs Portable

[In A Landy Down Under]

Sorry for yet another post on Solar (there are lots I have read many of them!), but need some specific help and also peoples opinions. Long Post alert as I would also like to learn a little along the way.

First off my specific set up:

Battery Set up.
1 x Bosch Primary Battery
1 x Optima Yellow Top (55AH)
1 x Remco AGM RM12-120DC (120AH)
1 x Redarc BCDC charger with solar regulator
These are running in parallel, with the Bosh and Optima sitting under the passenger seat of the Defender, and the Remco in the rear.

What Im running
1 x SnoMaster 85L fridge/freezer (and I do use the freezer as a freezer) (Power consumption between 1.6 - 5.5 amps)
1 x Baintech power board (for charging my phone, airbed pump, speaker, lights etc)
1 x ARB compressor (only currently used for tyre inflation but may add bed pump accessory soon)
1 x HD easy pull Runva Winch (never used)
1 x Nava Rear light bar (rarely used)
I also plan to run a small LED strip soon but I know that will use a very low amount of energy.

What im trying to achieve
My current set up allows me to stay on site for an estimated 48 hours without moving if everything is fully charged. Ive not properly tested it (because I daren't push another night out of it!) but it may last a little longer. What i would like to do is add a solar panel that will allow me to do 2 things.
1) Stay on site for 3-4 nights without moving (very unlikely to ever be 4 without moving at all, but I would like the option).
And more importantly, 2) Be able to hop from 1 site to the next with limited driving hours and not have to be concerned about driving for X hours just to recharge the battery enough to last the next spot. (Example, drive somewhere and stay 2 nights, then drive 3-4 hours and stay another two nights without fear of the power being completely drained)

Questions

1) From my understanding, whilst driving the alternator will be charging my batteries, but I have no idea how fast?! Does anyone know from (half) flat to (95%) full how many hours driving it would take for me to recharge my current set up?
I believe the batteries will shut off at around half capacity anyway, and I understand my Primary doesn't really come into this too much. My fridge also has an auto switch off mode when it reaches 10V, if this helps anyone.

2) As I would like to be able to rely more on the solar than the alternator to charge up my batteries whilst on my travels, my research tells me I should realistically be looking at a 150w-200w Solar Panel. This way I will be re-charging my battery at the same time, rather than just running it during daylight hours and using whatever the battery has left overnight. Would that be correct?

Fixed Vs Portable.
I think I do like the fixed panel for the 'set and forget aspect' but I also would prefer to park in shade anyway and run a cable to the optimum spot for sun with the solar...but thats only good if Im physically at my site (theft).....There's obviously lots of other pros and cons here, but maybe you can help me narrow it down. Im on a fairly limited budget (ideally under $500)

3) If I opted for a fixed panel on the roof rack, would the panel be charging my batteries at the same time as the alternator? Or will the batteries only accept the charge from the solar panel when the engine is off?

4) If I mounted a panel to the rack, and started going over some 'ruff-stuff' or corrugations.....would that not damage it with all the shaking and bumping around?? (Presuming I mount it solid enough for that not to be the underlining issue!)


I may have more questions as we go.....look forward to your responses and if im missing anything major or you just want to throw an idea my way please do.

Cheers

[Pedro_The_Swift]

One good limb drop helped cure me forever of camping under trees. [biggrin]
fixed. and yes it will help charge the vehicle while on the move

[weeds]

170amp/hr available should get you more than 48hrs......grab a cheap multimeter to check SoC

10v low voltage cut out is too low for my liking.

Do you really neeed a freezer, we easily go 7-10 days with out freezer, fridge only will extend our stay.

I had a 120 solar panel fixed to my roof rack for years....it survive the gulf and Simpson desert. I was going to change the fix hinge to a hinge that slides apart so I could park in the shade and run an extension cord panel to the sun but ended up removing the lot.

If you mount to the roof you will not get the max out of the panel, I had mine mounted at an angle and always parked facing north or multi days or face it east if pulling up late arvo for an overnighter.

We now have semi flexible panel that slide under the bed and pull them out when needed.

Depending on the amount of solar you purchase and can always start the car and let it run for awhile to top batteries up.

I’ve never have portable panels stolen when left in-attended.

Do you have storage available??

I would suggest getting a 160 folding set. Or two separate panels......fix one to the roof rack and have the other as back up or for when parked in shade. I fit Anderson plugs to all my 12v gear.

If you buy a folding set remove the hinges and catches, mount panel without reg to roof rack, leave the reg on the other panel but fit Anderson plugs so you can by-pass, this way you can add/plug it to the system on you car or if somebody with you needs a top up change the plugs around so the panel goes though the reg and hook up to 3rd party battery with aligator clips. We help a camper recently like this.

[In A Landy Down Under]

You are probably right weeds. I should really put it through a proper test.....but the freezer definitely eats a lot more power than the fridge (I have read anywhere up to 3-4 times?!). I will get a multimeter and see what its using then try do a mock-camp and see how it goes.

I do need the freezer, for bait primarily, but on my recent trip it was fantastic having an ice cream on camp in the 35 degrees heat!! :)

You say "10v low voltage cut out is too low for my liking." Why is that, I don't understand it all too much so just presumed that would be fine (being the lowest setting).

2 Panels has crossed my mind......but that will bump the cost up. I do have some space, but I'm always trying to reduce how much I take, or how much space it takes at least.

[DiscoMick]

Sorry for yet another post on Solar (there are lots I have read many of them!), but need some specific help and also peoples opinions. Long Post alert as I would also like to learn a little along the way.

First off my specific set up:

Battery Set up.
1 x Bosch Primary Battery
1 x Optima Yellow Top (55AH)
1 x Remco AGM RM12-120DC (120AH)
1 x Redarc BCDC charger with solar regulator
These are running in parallel, with the Bosh and Optima sitting under the passenger seat of the Defender, and the Remco in the rear.

What Im running
1 x SnoMaster 85L fridge/freezer (and I do use the freezer as a freezer) (Power consumption between 1.6 - 5.5 amps)
1 x Baintech power board (for charging my phone, airbed pump, speaker, lights etc)
1 x ARB compressor (only currently used for tyre inflation but may add bed pump accessory soon)
1 x HD easy pull Runva Winch (never used)
1 x Nava Rear light bar (rarely used)
I also plan to run a small LED strip soon but I know that will use a very low amount of energy.

What im trying to achieve
My current set up allows me to stay on site for an estimated 48 hours without moving if everything is fully charged. Ive not properly tested it (because I daren't push another night out of it!) but it may last a little longer. What i would like to do is add a solar panel that will allow me to do 2 things.
1) Stay on site for 3-4 nights without moving (very unlikely to ever be 4 without moving at all, but I would like the option).
And more importantly, 2) Be able to hop from 1 site to the next with limited driving hours and not have to be concerned about driving for X hours just to recharge the battery enough to last the next spot. (Example, drive somewhere and stay 2 nights, then drive 3-4 hours and stay another two nights without fear of the power being completely drained)

Questions

1) From my understanding, whilst driving the alternator will be charging my batteries, but I have no idea how fast?! Does anyone know from (half) flat to (95%) full how many hours driving it would take for me to recharge my current set up?
I believe the batteries will shut off at around half capacity anyway, and I understand my Primary doesn't really come into this too much. My fridge also has an auto switch off mode when it reaches 10V, if this helps anyone.

2) As I would like to be able to rely more on the solar than the alternator to charge up my batteries whilst on my travels, my research tells me I should realistically be looking at a 150w-200w Solar Panel. This way I will be re-charging my battery at the same time, rather than just running it during daylight hours and using whatever the battery has left overnight. Would that be correct?

Fixed Vs Portable.
I think I do like the fixed panel for the 'set and forget aspect' but I also would prefer to park in shade anyway and run a cable to the optimum spot for sun with the solar...but thats only good if Im physically at my site (theft).....There's obviously lots of other pros and cons here, but maybe you can help me narrow it down. Im on a fairly limited budget (ideally under $500)

3) If I opted for a fixed panel on the roof rack, would the panel be charging my batteries at the same time as the alternator? Or will the batteries only accept the charge from the solar panel when the engine is off?

4) If I mounted a panel to the rack, and started going over some 'ruff-stuff' or corrugations.....would that not damage it with all the shaking and bumping around?? (Presuming I mount it solid enough for that not to be the underlining issue!)


I may have more questions as we go.....look forward to your responses and if im missing anything major or you just want to throw an idea my way please do.

CheersI've had an 80 watt panel on my roof rack for two years and had nil problems.
You could also carry a second panel to connect using a lead and Anderson plugs.
No problems result from having both the alternator and panel charging while driving.
You don't need a DC-DC charger - just the regulators supplied with the panels.
Keep it simple - it's not that hard.

[trout1105]

I use portable panels and I haven't had any stolen But I usually don't park in crowded spots.
With the portable panels you have to set them up and move them twice a day to follow the sun which is a bit of a PITA But they will work much more efficiently that a fixed panel and you can park in the shade and the fridge and freezer won't have to work as hard and use less power.
Most modern alternators put out plenty of amps that will happily run a couple of fridges and keep your 3 batteries topped up at the same time while travelling so topping "on the run" using a fixed panel is probably overkill.
The advantage of a fixed panel is that it is set and forget and less prone to theft.
The advantage of portable panels is that they are more efficient, run cooler as they have a better air flow and you don't have to park under the full sun.
You can also pack the portable panels away when you come home.

[Pedro_The_Swift]

Crock,,,
if you park in the shade of an Ausie eucalypte you deserve all the branches you get,,

all panels are similar in performance,, its only different manufacturers that make a difference,,

If you run a 5-3 ratio ( example, 500W and 300 AH) then sun, rain, cloud doesnt matter, trust me about this....

Airflow is not a problem if you use the correct mounts,,

[Homestar]

Agreed, all panels perform about the same give or take but it's about the quality of the panel not the installation type, also I didn't notice any performance issues with my fixed mounting on ali angle in the hot mid 30's sun that everyone was so concened about - bought my batteries back up to 100% well before lunch. As Pedro said, 500 watts of solar and 300Ah of batteries will work fine even in the crappiest Melbourne Winter but I'm running a test now to prove this - I'm not going to plug my van into the mains at home and just let sun do it's bit over winter - I'll let you know if the fridge stops but I doubt it. (90 litre Engel)

And I won't park under a tree either. On a hot day, you're not in the van anyway and the fans I have in it can keep me cool fine even on hot night, so not bothered about the shade - I've got an awning for that. 👍😊

[trout1105]

One good limb drop helped cure me forever of camping under trees. [biggrin]
fixed. and yes it will help charge the vehicle while on the move

You don't have to park directly under trees to get the benefit of the shade, You can park strategically between 2 trees or even good sized bushes to get the benefit of the morning and afternoon shade without the problem of bits of the tree falling on your gear [thumbsupbig]

[DiscoMick]

You don't have to park directly under trees to get the benefit of the shade, You can park strategically between 2 trees or even good sized bushes to get the benefit of the morning and afternoon shade without the problem of bits of the tree falling on your gear [thumbsupbig]About three metres away from the outside radius of the branches on gum trees seems to be the go, I think, based on where branches land in our front yard at Maleny.