Hank the Tanks Dodgy battery and solar system

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Here's my thoughts Barry.
As campers go your use of 12v is pretty low and as you've come to realise you can manage without going for a huge lithium based setup. Having said that you've realised that you need more than 100Ah of storage to get you through those days with low/no sun, so 200Ah would probably be sufficient so adding another battery and then adding more solar IF needed makes sense on the face of it. Your problem is going to be when your batteries are a couple of years old and the capacity has faded to say 65% because at that point your 2 batteries are now only capable of storing little more than a single battery when it was new (like the one you're using at the moment) so you'll be struggling for capacity once again and therefore you'll be looking at replacing them quite regularly.
For a little more initial outlay you could buy 2 lithium off Amazon for just £170 each and just drop them in. Check the alternator charging current with a £20 DC clamp meter and if it's stupid high or stupid low (I doubt if it will be) then add a cheap B2B for £120 Inc cables.
You've now got a system that will effectively pay for it's self in just a few by years because you won't be swapping the batteries out every few years and will be upgradable with MPPT/ extra panels etc just like your LA system would have been.
Personally I'd upgrade to an MPPT anyway, it'll give you around 20-25% more solar and is a simple swap. There's loads of peeps swapping out their old MPPTs for larger ones as they install their mega lithium setups so you could pick up a cheap second hand MPPT with enough spare capacity for you to increase your solar in the future.
Lithium is now so cheap I really can't see the sense in buying and replacing Lead acid every few years.

Trouble with that is we are getting into the realms of stuff thats beyond me or that I would rather not mess with. If I go Lithium Im going for the system Off Grid Solutions proposed and ill let them handle it all. I really don't fancy me bodging it myself. I'm not messing about with Alternators etc and in the absence of anyone that can help me locally I think its best to either do what I am thinking and just whack in another 120 lead acid from Alpha or bite the bullet and go the whole hog. I think its worth trying my cheap idea first. If it doesnt work out so be it but its got to be better than what we had this year. In my experience the lead acid batteries we have had in the past worked pretty well for around six years before they started to go but then they went pretty quickly.

As for the controller I was always a big fan of MPPT and loved my old controller and really didnt like this one. Having said that, there is no doubt it does a good job and it charges the current battery pretty quickly. More importantly its connected to the engine battery also. It has a second output and it flashes when both are fully charged. I like that feature and as its already wired into the cab battery I think ill keep it.
 
Trouble with that is we are getting into the realms of stuff thats beyond me or that I would rather not mess with. If I go Lithium Im going for the system Off Grid Solutions proposed and ill let them handle it all. I really don't fancy me bodging it myself. I'm not messing about with Alternators etc and in the absence of anyone that can help me locally I think its best to either do what I am thinking and just whack in another 120 lead acid from Alpha or bite the bullet and go the whole hog. I think its worth trying my cheap idea first. If it doesnt work out so be it but its got to be better than what we had this year. In my experience the lead acid batteries we have had in the past worked pretty well for around six years before they started to go but then they went pretty quickly.

As for the controller I was always a big fan of MPPT and loved my old controller and really didnt like this one. Having said that, there is no doubt it does a good job and it charges the current battery pretty quickly. More importantly its connected to the engine battery also. It has a second output and it flashes when both are fully charged. I like that feature and as its already wired into the cab battery I think ill keep it.

I have the email of Eric who may be helpful Barry.
 

I have the email of Eric who may be helpful Barry.

Yes thats my old one. I loved that controller but it doesn't have a second output for the engine battery. It wasnt so much of an issue on the old van. If I parked up for weeks on end I would just disconnect the engine battery. This one will probably have a meltdown if I do that so I quite like the fact the controller has two outputs for charging.
 
With my super interlektool mind, I don't see why you couldn't have two controllers with two panels, keep the existing setup as is, and then have a new MPPt one connected to the new panel & the pair of batteries.

I'll sit back while someone tells me why that won't work.
 
I think the point is if I'm doing it myself to keep it as simple as possible.
 
That is simple, one panel controller and a battery.

Have you considered asking one of the members to help you fit it at a meet perhaps if one would be willing.
 
With my super interlektool mind, I don't see why you couldn't have two controllers with two panels, keep the existing setup as is, and then have a new MPPt one connected to the new panel & the pair of batteries.

I'll sit back while someone tells me why that won't work.
That would be fine.
Baz would probably be ok running both a PWM and a MPPT from a single panel too. I've also seen people running a PWM controller from the leisure battery to keep the cab battery topped up.
 
I sort of did the same on my self build and it did work, I just used a 10 quid pwm for the VB, and a good MPPT for the LB.

This was prior to combining them to get 330ah, then the MPPT took care of them.
 
I nnever stay away more than one night, i have 2 90ah lead acids votronic regulator 200w solar, all running a 230v fridge with a smart 600w inverter, led lights and a tv which we never watch much, ph charging and some times a 400w plug in heater, again seldom used, but no way would this work in deep winter if staying off grid for more that 2 days max, each van owner must work out his use and sort to there requirements.
If this is way beyond you then book in somewhere LOL.View attachment 137284
FLOWERY TWATS
 
When I built the transit ...

we ran 3 x 100ah flooded lead acid leisure batteries
2 x 100w panels
A £20 PWM controller
£40 durite vsr

3000w inverter

We ran a microwave
Kettle
Toaster
Slow cooker
Tv
Lights
etc etc ...

Never short of power in summer ....winter we moved around every couple of days

Current moho has

3 x 100ah agm
400w bifacial solar
MPPT
B2B
Victron monitoring
Mobile tinterweb
Victron eco mode inverter to run 240v fridge ....

Still never short of power
No electric cooking this time
Just
tv
Lights
Eberspacher

Winter we still move around ....

Point I'm making is there are many many ways to skin a cat and depends so much on personal usage ...

I always tell folks to work out WHAT they want to run a and for how Long off grid ...THEN work backwards to how you achieve that within a budget that suits .

I nearly went for Lithium BUT just couldn't stomach the cost at the point I was modding the van ....
Though the weight saving would've been nice ....

The 3 original fla batteries are now still doing duty on the greenhouse diesel heater ....7 or so years later .
And still hold a good charge despite having worked hard ....though looked after charging wise .

I rarely see our batteries go below 90% in summer time ....so I'm fairly convinced I've over specced things a 'bit' but I'm happy with that ....

Would I swap to lithium ?

At the moment only IF they were free lol
 
That is simple, one panel controller and a battery.

Have you considered asking one of the members to help you fit it at a meet perhaps if one would be willing.

Well its not. You were suggesting another panel and another additional controller. Thats not something I can do myself. However it would be possible for my motorhome fix it guy to fit another panel on the roof and we could put a better controller in. I am of the opinion though that the existing panel and one extra battery will do for our usage. I might be wrong but if I am then its not really an issue. Its still going to be way better than what we had this year and might just be adequate.
 
You need to remember that if you can't get power into them, you can't get any out.

But I can get power into them. I have a panel. Not sure of the wattage but I think its a 120. Maybe a 100 but its bigger than the 100 I had on the last van. Ideally I could do with another one if I double the batteries but my thinking was if it charged up a single one in next to no time then it will charge two still over the course of a day quite easily unless the weather is crap of course. The key factor is having a bit more spare if you get a couple of dull days. Any more than that then I guess we will be knackered but we will be moving about a bit more next year and hopefully in mainland Europe it will be sunnier! To be honest I bet we could just about get away with what we have over there.

In the old van we managed from April to September pretty well on one 120 AGM and a 100w panel. This one just needs a bit more I think.
 

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