Solar Panels - worth it?

I've got one of Rogers panels and a Victron MPPT 75/15 controller, all fitted by myself with no issues. I am a 30 years plus IT engineer (from back when it meant soldering stuff), so not afraid of getting stuck in to things like that. Certainly wouldn't say it was hard, not quite plug and play, but not far off. Took me maybe 3 or 4 hours going steadily at it, the hardest part was probably threading the cables through the various gaps.

Use the van for festivals where chance of hookup is zero and generally had no issues powering fridge, lights, internet and charging phones etc. Did find last year at a longer 10 day festival, where the panel was only getting sun in the morning (and not much on some over cast days), was struggling to keep the batteries charged so did run the engine a few times to top them up.

Wondered about a second panel but then thought that, particularly at festivals, optimal van placement to have the panel facing south might be an in issue. I also occasionally WFF (work from field) and need the ability to run a couple or laptops and that did eat battery. So....

Decided to get an Ecoflow River 2 Pro and 220w portable panel. With various discounts and stuff worked out about £900 which ain't cheap, but works absolutely brilliantly. I've added extra cabling so the portable panel can be wired in parallel with the roof one and potentially give me 320w, but in reality it's usually just over 200w and I think the controller won't use much more than that anyway. I can also charge the Delta 2 from the load output of the controller at the same time and potentially charge the vans batteries from the Delta 2 as well if required.
 
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Hi James,
I have a 230amp Fogstar underseat Lithium. But even with solar and a Victron dc to dc charger (instead of the original split charge relay) it can take a while to top up, especially if just solar. So again it depends on what your use is.
On the brightest most efficient day at best solar(200w) will only give 10-15aph.Engine charge included then maybe up to 30aph at best.

My 800w kettle draws around 70amps through an inverter, the air fryer maybe 85-90amps.

I don’t have a portable power unit but I am guessing (not sure) it charges via a 12v socket which would not give much more than 10amps I would think. A 100w solar on a good day maybe 7amps per hour. It would take a fair while to top up if you run any mains kit.

I do like the idea of the friendly pub for a plug in, especially if your portable unit has its own wheels.
All I'll be using power for will be the fridge and occasionally phone and garmin watch, nothing else so 100w should be fine. Kettle runs off gas. We're campers at heart so no air fryers, coffee machines, laptops or tv's. We only listen to music when travelling. Our Cali will be used as glorified b&b as once up and washed it'll be hike boots & rucksack on and out for day; snack lunch and either pub meal in evening or meal cooked on gas rings inside or portable gas stove outside. We'll then perhaps sup wine till late with wife reading or simply admiring the views whete ever we are while I may have head in map working out next adventure :)
 
All I'll be using power for will be the fridge and occasionally phone and garmin watch, nothing else so 100w should be fine. Kettle runs off gas. We're campers at heart so no air fryers, coffee machines, laptops or tv's. We only listen to music when travelling. Our Cali will be used as glorified b&b as once up and washed it'll be hike boots & rucksack on and out for day; snack lunch and either pub meal in evening or meal cooked on gas rings inside or portable gas stove outside. We'll then perhaps sup wine till late with wife reading or simply admiring the views whete ever we are while I may have head in map working out next adventure :)

Ideal setup.
 
I didn't think you needed direct sunlight but more daylight for them to work. They don't like getting too hot. I know that from my home one's which seem to generate the most first thing in mornings before it gets to hto at moment
In the shade they will give you about 0w. They need a clear view of the sky and the best is the sun. Further, the hotter it is the more power the fridge requires and the efficiency of the panels drops somewhat but the shade does not make up for that.
 
In the shade they will give you about 0w. They need a clear view of the sky and the best is the sun. Further, the hotter it is the more power the fridge requires and the efficiency of the panels drops somewhat but the shade does not make up for that.
interesting...
 
I've added extra cabling so the portable panel can be wired in parallel with the roof one and potentially give me 320w, but in reality it's usually just over 200w and I think the controller won't use much more than that anyway.
I’d be interested in understanding how you did this, I’ve also got a single 100w panel and the victron, already have a delta 2 which charges off the load side, have considered a portable panel to give me some options :)
 
In the shade they will give you about 0w. They need a clear view of the sky and the best is the sun. Further, the hotter it is the more power the fridge requires and the efficiency of the panels drops somewhat but the shade does not make up for that.
This was one of the reasons we upgraded to two panels from one; a single panel is adequate if you have a nice open pitch, but if you're forced to pitch under partial shade and only get direct sun for a few hours at most, then it means we can utilise the bit of light we get that bit more. If you're completely under trees, like you say, you get diddly squat no matter how many panels you've got. A few campsites we stayed on in France were like that, basically parked in a dense forest, lovely and cool but you'll need an alternative power source to solar if you're there for any length of time (unless you have a solar panel mounted on a 20m telescopic pole you raise above the tree canopy).
 
In the shade they will give you about 0w. They need a clear view of the sky and the best is the sun. Further, the hotter it is the more power the fridge requires and the efficiency of the panels drops somewhat but the shade does not make up for that.
Hmmm... not always unless you really have deep cover. I've noticed my panels on my home still generate reasonably well on cloudy overcast days and right up till sunset when sun it behind trees going down. It does depend on how good the panel and controller are so I can't give any opinion on the ones on a Cali, only my home. Yes I understand fridge works harder when sun out in full in summer but you're also generating more power. For my use I won't be stopping under trees anyway as bad idea in UK with weak branches and in any case hwn we travel it's never that hot.
 
Get one of these and plug one end into leisure battery 12v plug, the other into 12v engine battery plug. It will trickle charge engine battery from leisure.

I thought I could remember reading somewhere in my early days of Cali ownership, that when the leisure batteries were "topped up" by solar, the leisure batteries then trickle charged the vehicle battery.
Did I dream this and is this then total b*llocks?
In my defense, I read so much stuff in my initial info-gathering stage of ownership, that I could have got confused :talktothehand
 
I thought I could remember reading somewhere in my early days of Cali ownership, that when the leisure batteries were "topped up" by solar, the leisure batteries then trickle charged the vehicle battery.
Did I dream this and is this then total b*llocks?
In my defense, I read so much stuff in my initial info-gathering stage of ownership, that I could have got confused :talktothehand
I think Rogers website says similar as well from memory, either that or that the is a trickle charge from the solar to the starter battery, but only about 1 amp (?) i'll have to go back to his website to make sure
 
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I thought I could remember reading somewhere in my early days of Cali ownership, that when the leisure batteries were "topped up" by solar, the leisure batteries then trickle charged the vehicle battery.
Did I dream this and is this then total b*llocks?
In my defense, I read so much stuff in my initial info-gathering stage of ownership, that I could have got confused :talktothehand
It does on T5.1/6 but not by design. VW says No , but I've proved it to my satisfaction. Regularly park at Heathrow for 5 weeks or so and always starts.
 
Are the panels sturdy at motorway speeds? through Germany 160 and sometimes to 180km/h is what I usually do. These vans move!
Speedy! You are getting close to the maximum speed rating of some factory fitted tyres there. 3000kg at 180km/h is a lot of kinetic energy. Hope you have the larger brakes fitted.
 
That's obviously handy to know.......................
 
'wonder how long before someone invents solar power lawn mower'.........(you can see we have interesting chats lol!!! Is there one yet..................................
Google suggests there are loads of them, from no-name through to Husqvarna.
 
I thought I could remember reading somewhere in my early days of Cali ownership, that when the leisure batteries were "topped up" by solar, the leisure batteries then trickle charged the vehicle battery.
Did I dream this and is this then total b*llocks?
In my defense, I read so much stuff in my initial info-gathering stage of ownership, that I could have got confused :talktothehand

It depends on the individual van, as for some unknown reason VW did not wire them all the same - hence no fuse diagram in the manual!. Some vans do, some don’t. Easiest way to check is to get 2 plug in voltage meters (and see if the engine shows a charge voltage when not running / on EHU, when leisure battery is fully charged).

I now have a T5.1 Club Joker, engine charges when leisure has surplus.
 
It depends on the individual van, as for some unknown reason VW did not wire them all the same - hence no fuse diagram in the manual!. Some vans do, some don’t. Easiest way to check is to get 2 plug in voltage meters (and see if the engine shows a charge voltage when not running / on EHU, when leisure battery is fully charged).

I now have a T5.1 Club Joker, engine charges when leisure has surplus.
Apologies for being an electrical numpty, but I don't quite get the principle of using 2 voltage meters, so I'm unsure as to how to go about using both to test if the vehicle battery is receiving a trickle charge :talktothehand
I guess one would go on the vehicle battery, but does the other one of the leisure batteries?
If you would be able to give some detailed how-to, it would be much appreciated. Thanks
 
Apologies for being an electrical numpty, but I don't quite get the principle of using 2 voltage meters, so I'm unsure as to how to go about using both to test if the vehicle battery is receiving a trickle charge :talktothehand
I guess one would go on the vehicle battery, but does the other one of the leisure batteries?
If you would be able to give some detailed how-to, it would be much appreciated. Thanks

Something like this plugged into cigarette socket will allow you to see voltage. You can do it with one, but with two you can easily monitor both at the same time.

Rear sockets are leisure, one dash socket will be engine (2nd dash socket can be engine or leisure according to year!)

IMG_0799.png
 
Something like this plugged into cigarette socket will allow you to see voltage. You can do it with one, but with two you can easily monitor both at the same time.

Rear sockets are leisure, one dash socket will be engine (2nd dash socket can be engine or leisure according to year!)
Except on our MY23 I discovered (after much initial confusion) every 12v socket on the vehicle is leisure; the one by the gearstick, the one on the dash-top, the one next to the sliding bench and the one in the boot. On the drive, engine off, they were all reading 13.7v (solar panel was on float); a voltmeter on the van battery confirmed 12.7v (and I checked and confirmed the plug-in voltmeter was accurate too), so they're definitely all connected to the leisure battery. Bit frustrating actually as I wanted to measure the vehicle battery easily!
 
Something like this plugged into cigarette socket will allow you to see voltage. You can do it with one, but with two you can easily monitor both at the same time.

Rear sockets are leisure, one dash socket will be engine (2nd dash socket can be engine or leisure according to year!)

View attachment 125560
Now, I am confused as to what I need to do, :sorry
 
Except on our MY23 I discovered (after much initial confusion) every 12v socket on the vehicle is leisure; the one by the gearstick, the one on the dash-top, the one next to the sliding bench and the one in the boot. On the drive, engine off, they were all reading 13.7v (solar panel was on float); a voltmeter on the van battery confirmed 12.7v (and I checked and confirmed the plug-in voltmeter was accurate too), so they're definitely all connected to the leisure battery. Bit frustrating actually as I wanted to measure the vehicle battery easily!
I'm even more confused now :sorry
 
All of the cigarette 12v sockets behind the front seats run off the leisure battery, the ones in front run off the starter battery.
 
All of the cigarette 12v sockets behind the front seats run off the leisure battery, the ones in front run off the starter battery.
Not in my case, see above. Tested with a voltmeter when the leisure was on float and the vehicle battery was sitting at rest at 12.7v. I was sufficiently confused to double check with a proper voltmeter (as opposed to a plug-in one) and it agreed. All four of the 12v sockets on my van are leisure-powered.
 
I’d be interested in understanding how you did this, I’ve also got a single 100w panel and the victron, already have a delta 2 which charges off the load side, have considered a portable panel to give me some options :)
It was quite simple, basically added some extra XT60 connectors - the same as the solar panel input on the River 2.

I bought a short 40cm XT60 male to female extension and cut it. The roof panel cable now has the female connector and short bit spliced on the end, the Victron input has the rest of the lead with a male so they can connect directly to each other as before if needed. I then got a single female to double male Y splitter (eBay link below) and put that between them so that I now have an extra male connector I can connect the external panel to.


As it's an Ecoflow panel, it already has an XT60 connector on the cable although obviously you don't need to buy theirs, it just suited me to keep it all the same so I can mix and match as required using a few other cables, extensions etc. In theory could connect from the 12V output of the Delta 2 to the new splitter and charge the van batteries rather than plugging into the EHU. I think it should be more efficient but I'd guess much slower as current would be lower.

One thing is the River 2 (and panel) have a slightly different XT60 connector on, and XT60i. It's orange with what looks like an extra earth pin, from what I can find, it allows more intelligent connection between the Delta 2 and whatever source so it can carry up to 100A (as opposed to 60A on the standard cables). Given were going nowhere near those numbers (the Victron is 15A max), I don't think it's relevant and the internet seems to generally agree.


PXL_20240702_171127186.jpg
 
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Not in my case, see above. Tested with a voltmeter when the leisure was on float and the vehicle battery was sitting at rest at 12.7v. I was sufficiently confused to double check with a proper voltmeter (as opposed to a plug-in one) and it agreed. All four of the 12v sockets on my van are leisure-powered.
Same. The mid to last 6.1 all the same. Not sure when VW made the switch. Caused confusion at first when I was monitoring starter via the front 12V and it was reading the same as leisure.
 

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