Anyone using a solar setup for leisure battery?

[matt1458]

My split charge relay has after 3 years decided to screw up my start stop system (really should have realised normal Durite split chargers and start stop do not mix in advance)

But considering the low mileage, I’m thinking of fitting a solar setup instead just to keep the battery reliable, especially on weeks where it’s big commercial work and the van is stationary for large parts of the day.

Anyone using a solar system? I’m looking at a 140W Victron smart solar kit. Any advice if 140W is enough or if bigger panel required?

There’ll be one 110AH battery on the other end running up to 2 pumps / controllers (although 90% of the time only 1 pump / controller)

Based in South East England (where in theory it’s sometimes quite sunny) if that makes any difference

 

[spruce]

My split charge relay has after 3 years decided to screw up my start stop system (really should have realised normal Durite split chargers and start stop do not mix in advance)

But considering the low mileage, I’m thinking of fitting a solar setup instead just to keep the battery reliable, especially on weeks where it’s big commercial work and the van is stationary for large parts of the day.

Anyone using a solar system? I’m looking at a 140W Victron smart solar kit. Any advice if 140W is enough or if bigger panel required?

There’ll be one 110AH battery on the other end running up to 2 pumps / controllers (although 90% of the time only 1 pump / controller)

Based in South East England (where in theory it’s sometimes quite sunny) if that makes any difference

Please explain. There are lots of windies running stop start vans without reporting issues.

A windie in the Southampton area tried solar panel charging about 7 years ago, maybe longer. (The old panels did require sunshine, but they tell me the latest panels work with daylight. This is according to my son who knows everything and his old dad knows nothing. ) It worked during the latter Spring to early Autumn period, but some days during winter he only managed an amp when the weather was bad. He also had a Victron MPPT controller rather than a cheap PWM controller.

One of the drawbacks to solar during winter they tell me is the angle of the sun on flat solar panels. How have you found the 100 watt solar panel performs in winter @AW Services

@AW Services response:

I would recommend investing in a PV solar system.
When I first moved into wfp the issue I had was lack of mileage from home to jobs.
Start stop journeys kills any van starter battery and also has a knock on effect if using a spilt charger system.

I was monitoring my leisure battery constantly and not allowing it to deplte or drop below 11v
I charged my battery every night with the hook up I installed. Yes it's a right faff unplugging it every morning.

I had installed many solar pv systems into friends DIY offgrid camper vans and thought why don't I do the same.

I have a 100w solar panel on my roof bars fixed with an aluminium frame I welded for stability
A victron MPPT charge controller, inline fuse and that charges my leisure battery system and also charges my vans starter battery through the Durite split charge system ( split charge relays are two way)

Understanding battery usage and thresholds is key. If my memory serves me well then @spruce published a post a few years ago on voltage Vs percentages and battery charge status which is a good tool to know how good your battery is.

My panel is slightly ramped up at around 20 degrees and I've not had any major issues with charge current and battery health. It's always at 12.8 volts which is nice to see. If you are good with electronics you can cheat a little with a buck converter. I've also etched some pcbs and added diodes to ensure my split charge system doesn't create any adverse reverse current into the charge controller.

I also park my van under my neighbours led floodlight that's always on at night 50w of led equals extra charge at night

There have been a few posts over the years regarding solar panel charging. A search "leisure battery charging solar" will find some of these. @matt1458

 

[ched999uk]

I'm not running solar for window cleaning but have had solar on a motorhome and at home.

I would say you would get a max of about 8 amps during the height of summer. Dropping to about 10% of that on dull days.
Solar panels and Victron mppt controllers are relatively cheap these days - https://uk.renogy.com/products/solar-panels/rigid-solar-panels/ 100watt panel is only £70. I would be inclined to get 2 x 100watt panels or as much as you can fit on the roof. In the summer you will be generating way too much but in the winter you might be OK.

 

[matt1458]

Please explain. There are lots of windies running stop start vans without reporting issues

As was I for the last 3 yrs, it was a brand new van in 2020, installed a standard Durite split charger and thought nothing more of it.

Recently a world of fault codes appeared (although nothing that affected actual van use just engine fault warnings) had a tame mechanic mate plug it in and clear everything down, restart it and immediate fault reappears, start stop now inactive and unable to enable / disable (not that it particularly bothers me because I’m no fan of start stop).

On further investigation turns out the normal Durite chargers aren’t designed for stop start engines with these “smart” stop start alternators or whatever they’re called, what’s actually required is a specific type of DC-DC charger. Victron do them, I’m no expert at all but have spoken to enough people to understand there’s a specific type of split charger that is fully compatible with start stop.

Looking at the price there’s not much in it vs having one of those vs a solar setup, bearing in mind the van has done 17k miles in coming up for 4 years I can’t imagine the split charger is really bringing a huge amount to the party, especially on weeks where it’s stationary for the majority of the day, I figure any charge is better than zero charge!

 

[matt1458]

I'm not running solar for window cleaning but have had solar on a motorhome and at home.

I would say you would get a max of about 8 amps during the height of summer. Dropping to about 10% of that on dull days.
Solar panels and Victron mppt controllers are relatively cheap these days - https://uk.renogy.com/products/solar-panels/rigid-solar-panels/ 100watt panel is only £70. I would be inclined to get 2 x 100watt panels or as much as you can fit on the roof. In the summer you will be generating way too much but in the winter you might be OK.

Yeah this is what I’m thinking, I’m not expecting miracles and I’m happy to top it up in the winter, but for days mid “summer” we’re parked up in a school grounds for the full day for example it would be nice to know at least something is feeding the battery etc

 

[AW Services]

My split charge relay has after 3 years decided to screw up my start stop system (really should have realised normal Durite split chargers and start stop do not mix in advance)

But considering the low mileage, I’m thinking of fitting a solar setup instead just to keep the battery reliable, especially on weeks where it’s big commercial work and the van is stationary for large parts of the day.

Anyone using a solar system? I’m looking at a 140W Victron smart solar kit. Any advice if 140W is enough or if bigger panel required?

There’ll be one 110AH battery on the other end running up to 2 pumps / controllers (although 90% of the time only 1 pump / controller)

Based in South East England (where in theory it’s sometimes quite sunny) if that makes any difference

I've got a high efficiency Photonic Universe 120W monocrystalline solar panel paired with a victron 100/20 MPPT charge controller and 120aH Numax deep cycle leisure battery and a few extra accessories such as a 1500w pure sine wave inverter, mains hook up and sockets

Charges my battery for work purposes and great for my camping weekends away

I've tig welded an additional panel mounting frame with a 15 degree so that my panel isn't sat flat and captures plenty of sunlight in both summer and winter and I tend to park appropriately to maximise my input

It all retrofits onto my Rhino roof bars using clamps

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