MPPT controller or larger solar panel?

[colinm]

I was merely trying to be helpful. If I offended, I do apologise.

No problems, whilst I have decades of experience of using Solar, I'm only experienced (and interested to any great extent) in what works for me, so I'm no expert esp. on bigger systems.
I suspect if the OP wants a 'cheap' upgrade, then it might be better to get another 120w panel and wire it in parallel, it won't be the most efficient but might do the job with minimum outlay, this might also lend itself to a future upgrade to MPPT and wiring in series, but more experienced members might be better to advise on this.

 

[Markd]

Yes there is a third option of adding an extra battery and if you are a low user that might be all you need for a few days at this time of year and longer in the summer - add in some travelling and you are quids in.
However if you want to full time you will probably want all 3 especially if 300w panel exceeds existing controller capacity or voltage rating.
if you have the space ADD 300w panel!!

 

[mistericeman]

We ran quite happily with 2 x cheap 100w panels and a £20 pwm controller in the transit along with a Durite VSR charging 3 x 100ah FLA leisure batteries ....
And never needed hook up (we move around pretty much every day) Despite being heavy users as all cooking was electric along with eberspacher D2 running 24/7 when away in winter...

Decided to go with a 400w bifacial panel and Ring rscdc30 solar controller/B2b Charger in the Moho along with 3 x 105ah AGM batteries...

Have I gone the right way?

Early days yet lol... BUT we will see I guess in the fullness of time,bearing mind we won't be as heavy users.

 

[Phantom]

I suspect if the OP wants a 'cheap' upgrade, then it might be better to get another 120w panel and wire it in parallel, it won't be the most efficient but might do the job with minimum outlay, this might also lend itself to a future upgrade to MPPT and wiring in series.

More along the lines of a cost effective upgrade. A 300w panel can be had for about the same as a 120w panel.

 

[Phantom]

Yes there is a third option of adding an extra battery and if you are a low user that might be all you need for a few days at this time of year and longer in the summer - add in some travelling and you are quids in.
However if you want to full time you will probably want all 3 especially if 300w panel exceeds existing controller capacity or voltage rating.
if you have the space ADD 300w panel!!

We have two good leisure batteries, are full timing, and seem to be managing for a few days depending on solar - though some travelling helps. All three is the ultimate solution. We could relocate the 120w panel and add a 300w, but will likely just use a single 300w or so panel.

 

[Phantom]

We ran quite happily with 2 x cheap 100w panels and a £20 pwm controller in the transit along with a Durite VSR charging 3 x 100ah FLA leisure batteries ....
And never needed hook up (we move around pretty much every day) Despite being heavy users as all cooking was electric along with eberspacher D2 running 24/7 when away in winter...6

Decided to go with a 400w bifacial panel and Ring rscdc30 solar controller/B2b Charger in the Moho along with 3 x 105ah AGM batteries...

Have I gone the right way?

Our current set up is similar to your Transit one but less. Could go more on solar but about a 300w panel, MPPT, and our current batteries should be sufficient for a bit heavier power use around winter.
You've gone a good way and should give you piece of mind.

 

[colinm]

More along the lines of a cost effective upgrade. A 300w panel can be had for about the same as a 120w panel.

Looking at the recommended installation for a couple of these 300w panels, and for12v you will need a MPPT regulator. You don't say what PWM regulator you have, so don't know if this would need changing if you added a 120w panel in parallel.
Note that it has been posted before that cheap 'evil bay' MPPT regulators are often PWM, so to be safe with the 300w panel you will need a well respected make.

 

[Markd]

I would recommend Votronic because they have a secondary trickle charge for the starter battery.
Whilst not essential if you drive frequently it's very handy when parked up for any length of time.
They do 350w and top unit is 430w

 

[Sailorpedal]

I find a little generator works best for me.