Adding to Existing Go Power Roof Mounted Solar Panel on Geo Pro.

Updated 01/22/2025 | Published 07/30/2021

Products Featured in This Question

Go Power MC4 Output Cable with Male and Female Connectors - 30' Long

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$31.99

Go Power MC4 Output Cable with Male and Female Connectors - 10' Long

(47)

$15.99

Go Power MC4 Output Cable with Male and Female Connectors - 15' Long

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$20.33

Go Power Overlander Expansion Kit - 200 Watt Solar Panel

(108)

$374.39

Question:

If my trailer has a 190 W panel on the roof top, with a 1000 W inverter and the charge controller....but it also has a port for solar-on-the-side- how large of a portable kit can I add to my system? The sticker on the side port says 20 amp maximum, but the 200 w rigid panel kit is described as a 30 amp charge controller, while delivering 11.6 roughly amps in full sun. My existing panel could be delivering 9.3 amps in full sun. So adding those together is 20.9 amps.... is that too much? Or do I not need to add in the 9.3 from the roof panel? And lastly, if I did upgrade with the 200 w panel set, how many batteries would be required? I am planning to switch my one 12v flooded to two 6v in parallel.

asked by: Steve

Expert Reply:

Adding solar panels and building a battery bank for off-grid camping camping is great, we can definitely help with most of the items needed for this. If your Geo Pro already has a fixed 190W panel mounted to the roof running through a 30 amp charge controller then you are off to a good start. It sounds as if you are prepped for ground deployed solar in addition but the wiring used is rated for 20 amp max, I would not exceed the rating. You need to verify that the ground solar prep does run through the current controller, if so you will add any additional amp from the ground deploy panels to the existing fixed mounted panels for total value. Yes, under optimal conditions this would place your value at a slightly higher value than max rating. I think you will be okay since one rarely is able to pull the max. However, if you are in a situation where you can draw max, monitor it and adjust the ground deployed panels in a way that they do not draw max. a benefit of the situation have is with something such as the Go Power Portable Solar Panel, # 34282610, you can park camper in available shade and use the ground deployed panels in the sun.

Another option is to use the expansion kit to increase the solar power of your current Go Power setup with a second fixed mounted panel. For this, we have the 190 watt kit part # 34282182 available with different extension cables depending on what is needed, # 34276216 for 10 feet, # 34279532 for 15 feet, or # 34276215 for 30 feet.

When matching your solar power to your battery bank there it is not that there is a requirement of X battery to Y solar panel capability. It is that you want to balance your capability to recharge your battery bank against usage. There is no need to oversize your solar panels relative to your battery bank unless you want to ensure you have a fully charged bank in a short amount of time. Conversely, it is best to have enough solar to replace the energy used from your battery bank during the limited day light hours.

With the set-ups discussed above, you will have approximately 400 watts. If going with something such as the 6V golf cart battery, personally, I would consider 4 batteries in the neighborhood 0f 200-225Ah.

I have attached a couple of help articles, please see links below. Let me know of any follow-up questions you have. Happy Camping!

expert reply by: Michael R

Mad M.

3/21/2024

I am a geo pro 15 tb owner and can confirm that the solar on the side runs directly to the battery so controller required

Arby

10/15/2024

I am considering adding an additional panel and connecting via the "Solar on the Side" port. Based on the voltage measured at the port, I am seeing the voltage that is being output by the 200w roof panel (20.3 v), and confirmed on the Firefly panel (20.3 v); house battery voltage at Firefly display is 13.4 v. This leads me to believe that the port is connected to the solar side of the charge controller. If this is the case, am I able to connect solar panels directly into the port (no charge controller, in what would probably be a parallel configuration)? I have the SAE to MC4 adapter that came with my RV, so it should be straight forward connection. Any precautions before connecting additional panel? Thank you.

Jameson C.

10/15/2024

@Arby Yes you should be able to connect another panel in parallel to what you have now and it will then go to your current controller and provide you with additional solar power.

Guerryb

1/22/2025

@JamesonC No, because the solar on the side port is wired directly to the battery, as pointed out in a previous comment. It is in no way connected to the roof mount solar panel and controller.