Solar and 12V system plan

With loads like induction hobs, it’s hard to see solar input keeping up with the long term drain outside of fairly specific (high sun, little cooking) scenarios. Given this, you’re converting diesel to electric to cook through the DC-DC, so there’s an argument for bypassing the expensive electric bit and just using the diesel directly in a diesel hob.
 
Thanks for that.
The triple charger does seem to tick all the boxes, whilst it is a case of all your eggs in one basket, it does look like a great basket.
I like that it also trickle charges the starter battery & I wouldn’t have to find a home for the ac to dc charger when the EHU goes in sometime in the future...
Hmm, just when you think your nearing a decision...
 
With loads like induction hobs, it’s hard to see solar input keeping up with the long term drain outside of fairly specific (high sun, little cooking) scenarios. Given this, you’re converting diesel to electric to cook through the DC-DC, so there’s an argument for bypassing the expensive electric bit and just using the diesel directly in a diesel hob.
With 200ah we can last for 3/4 days in the winter and with sun in the summer indefinitely. That said to supplement our 250w panel on the roof I did just by a renogy 200w folding suitcase panel at a steal of a price thanks to the recommendation of @Dellmassive. This is for if we stay in one place for a bit longer and park in a shaded area.
 
Hi
So, I finally got round to reading this properly... are you running the fridge from the inverter too, or is it a 12V?
Mine is a Dometic cool box style and uses only 0.5ah/h, so about 12Ah per day, I can see that kicking up in warm weather to maybe twice that.

So finally getting up a ladder to the van roof with a tape measure in hand is quite sobering, the ridges on the roof don't help...
I reckon to get two panels side by side lengthways they'll have to be between 400 to 490mm wide to sit onto the outer 3 ridges.

Narrowest I've found so far are 505mm wide & might work with the edge carefully filleted with adhesive... lots of masking needed here tape!
Photonics Universe (PU) do a 130W in this width with the circular rear junction box, which will keep the roof lines clean & drop nicely through the middle of the three ridges.
A pair of these gives 260W and comes out at £1.86/w

Going to a single panel is the next option.
PU do a 180W which is 665mm wide; this will site nicely on the middle 4 ridges, though the rear cable junction box will sit in the central trough, so will need some care to ensure a seal; I'm imagining a PU closed cell foam gasket around it, which I'd back fill with sealant from the inside; I'd appreciate comments.
Cutting this out of cardboard and laying it on the roof is pretty sobering too.
180W at £1.83/w

I'm currently leaning toward the twin panels; gets 44% more power and better shading resilience.
FYI Turns out the narrow PU 130W doesn’t have the rear cable outlet.
 
With 200ah we can last for 3/4 days in the winter and with sun in the summer indefinitely. That said to supplement our 250w panel on the roof I did just by a renogy 200w folding suitcase panel at a steal of a price thanks to the recommendation of @Dellmassive. This is for if we stay in one place for a bit longer and park in a shaded area.

Is that without using the induction hob though or did I misread your earlier post about not using it?
 
Is that without using the induction hob though or did I misread your earlier post about not using it?
That’s without the induction hob - as we do not cook in our van. Use the microwave, toaster, coffee machine and charge 3x iPhones, iPad, surface, headphones. Have lights on in the evening. Etc.
 
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That’s without the induction hob - as we do not cook in our van. Use the microwave, toaster, coffee machine and charge 3x iPhones, iPad, surface, headphones. Have lights on in the evening. Etc.
So I'm guessing your typical demand is dominated by the fridge then; what type do you have?
 
This one,

Thanks, I hope we can compare notes over a beer or three in Sibertoft next month
 
Cable Entries.

The ones offered by the panel companies all seem similar & to me, quite ugly.
So I went looking in the marine sector (should be waterproof then) and found these IP68 rated ones...

SE1B-3.jpg

in my eyes there much neater and seem cheaper too...

Index Marine side entry cable gland
 
So I’ve bitten the Lithium bullet and ordered one of those Roamer under Seat batteries.... the life vs depth of discharge data looks good with >7000 cycles at 80% DoD.
Steve at Roamer is being very helpful despite being away on holiday somewhere!

I’ve also decided on 2x 150w barrow panels from Photonics Universe...

Just the electronics to decide on now...

The Victron stuff looks good but is pretty pricey; my question is...
Is it worth it? & why?
Cheers
 
So I’ve bitten the Lithium bullet and ordered one of those Roamer under Seat batteries.... the life vs depth of discharge data looks good with >7000 cycles at 80% DoD.
Steve at Roamer is being very helpful despite being away on holiday somewhere!

I’ve also decided on 2x 150w barrow panels from Photonics Universe...

Just the electronics to decide on now...

The Victron stuff looks good but is pretty pricey; my question is...
Is it worth it? & why?
Cheers
Hi… I went with Ctek as its a dual system …but when I upgrade I’m looking at REDARC (Australian) again duel input …based on cost and simplicity…it’s available from 12v Planet & Travelvolts….:)
 
I’ve looked at the Redarc and the 50A is one of the highest of the combined units I’ve seen so far.
I guess it’s about how long you’re driving to top up the battery at those ends of the year when the solar just isn’t enough.
I’m in discussion with Renogy about using a pair of DCC 50’s side by side.,. One just doing battery to battery (so giving it’s full 50A) and the second doing battery to battery and solar so a max of 25 A from each. My solar will rarely hit 25A (mid day in south of Spain in July...) and that should give up to 75A from the alternator if needed for uk autumn greyness.... we’ll see!
I may need to upgrade the installed cable from the starter for that system!
 
ps with a bit of re-wiring they can keep it going if one dies too.
 
ps with a bit of re-wiring they can keep it going if one dies too.
As a thought Travelvolts will give you free advice and are a trusted member….I sure if you explain your needs they may offer a different solution….the problem for us all is fitting the right setup with some level of future proofing

ps… they also understand Transporters…always a plus point :thumbsup:
 
+1 for Redarc gear. Expensive initial cost but generally trouble free. I run a Redarc bcdc mppt dual charger, and solar panels, 1 fixed on the roof and a couple of solar blankets. Total 500w if needed.
When I had trouble with the 150w blanket , even though it was out of warranty by 6 months or more they replaced it.
Many people run Redarc gear in Australia and its seen as the gold standard.

One thing I have learned is fridges pull a lot more power in hot weather as the compressor runs heaps more and when back in cooler temperatures compressor hardly runs at all. For this reason its better to use higher spec mppt gear than you think you need as you may need more panels due to when the sun shines on your van the solar output is good but fridge running uses a lot of this as interior heats up quickly causing compressor to consume a lot of power from your battery.
Often when temperatures are low it's also cloudy so solar input is low so not much going into battery so even though fridge isnt running as often you can still start running low on battery reserve.
It can be a balancing act, so going lithium lifepo4 battery and the option of more panels is a good idea.
This may be only relevant to you if you want to be able to stay off the grid when travelling to places in hot climates. Most of us seem to initially underestimate our power needs and often have to beef up later on so being able to start out with an expandable system can work out cheaper in the long run.
I spend most of my time off grid when travelling so this may not be relevant to you but thought I would point it out.
 
As a thought Travelvolts will give you free advice and are a trusted member….I sure if you explain your needs they may offer a different solution….the problem for us all is fitting the right setup with some level of future proofing

ps… they also understand Transporters…always a plus point :thumbsup:
Thanks for that, I’ve sent a invite to here via pm.
 
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