Parallel solar setup

[TheEL]

Pardon my ignorance but Im not super well versed in this.

I currently have a 150w panel on my van with a victron mppt 75/15 charging a 100ah battery.

Could I in theory get a foldable 200w solar panel and wire it in parallel when Im parked with my 150w panel to my charge controller and charge my battery without blowing anything up? Anything of concern with that setup?

Any help or insight appreciated.

 

[TheEL]

Yes! Thank you. You and Mr.Google have steered me down the right path I believe.

 

[Alloy]

This is similar (not the same due to difference in the solar panle Vmp**) to something called over paneling which is done because solar system are often at less than peak output.

**Vmp (Voltage@Maximum Power) is the maximum voltage when connected to a load.

The advantage is $ savings on a second controller,wiring ,fusing and extra space needed.

The negatives is the controller is running more (OK for a quality controllers/bad for a cheap controllers) at peak output and there's no redundancy.

 

[FAW3]

A real-life example of what you're trying to do: We have a Four Wheel Camper truck camper that has a 160 watt panel on the roof. I have a 100ah lithium battery in the camper. The panel works great in most situations...but when parking in the shade, or after a series of cloudy days, or the winter the low sun angle and I find my battery is not being suitably charged.

I added a Bluetti 120ah foldable solar panel set and an extension cord run into an auxiliary solar plug receptacle on the camper. The OEM solar controller handles both panels. When needed as indicated by the state of charge via the solar controller panel, we use the extra panel. It's been great and we find we use it about 10-15% of the time.

Works great and provides just the "solar boost" we needed. Much more flexible range of use over adding another fixed panel on the roof. We park where we want and run the panel and cord where the sun is. No regrets over the purchase.

 

[TheEL]

4. Battery Capacity: Verify that your 100Ah battery can handle the increased charging current from the combined panels. It's important to ensure that the charging rate does not exceed the battery's recommended limits.

This is a concern I want not aware of. Sounds like the max charging current for a 100ah battery would be 10A.

I was looking into getting this setup:

Renogy 200 Watt 12 Volt Portable Solar Panel with Waterproof 20A Charger Controller, Foldable 100W Solar Panel Suitcase with Adjustable Kickstand, Solar Charger for Power Station RV Camping Off Grid​

I like that I can attach it for more power harvesting as needed AND it comes with its own charge controller.

My question now is if I have my current charger controller set to max charge current at 5A and the renogy aux panels set the same at 5A max charge current would that make it safe to be at the 10A max charge limit?

 

[rruff]

This is a concern I want not aware of. Sounds like the max charging current for a 100ah battery would be 10A.

It's 100a, not 10a. No worries.

The charge controller would be the limiting factor, but if you plan to use the PWM that comes with the portable panel, that will be fine also.

You can connect mismatched solar modules in parallel to a charge controller.
The array will capture more energy than either module would capture individually.
But its poorly efficient.
In your scenario you will capture somewhere over 200W, but nowhere close to the 350 total of your individual modules.
To maximise capture, use a controller for each module.

I am sure Mr.Google can direct you to learn more about "mismatched solar modules connected in parallel"

There is no problem at all with size miss-matched parallel strings in one controller, if the panels have the same voltage specs.