question,, which is better when looking at solar panels.??

Up to about 360 watts or 30 amps, 12 volts and a PWM controller is better. Those would be 12 V panels, and you be concerned about what the lsc or amperage during short circuit reading is, the higher the better. 18V under max load is good, 17.0V under max load would be better, the amperage rating would be higher. This is all for 12 Volt rated panels. I'd also insist on Poly crystalline panels, not mono panels.

carl2591 wrote:
this of for airstream RV 30 fter. In reading jacks and handy bobs site I sorta see where the higher voltage panels, even with the lower amps, are most likely the better choice.

As said, watts= volts x amps. Your controller will figure it out.

Higher voltage is a good choice.

this of for airstream RV 30 fter. In reading jacks and handy bobs site I sorta see where the higher voltage panels, even with the lower amps, are most likely the better choice.

higher voltage = smaller wire = less weight = lower cost for wire and smaller hit to CCC of trailer. win win win.

right now looking to go with mppt controller either morningstar 30 amp w bogart meter or bluesky SB3024DiL with pro rn remote display going to what is now 2-12v volt (not sure Ah don't have TT yet) deep cycle type batteries, which will be change out for 2 6v golf cart crown or US batteries type units in the future.

the 195's are a bit larger (5" wider and 5" longer) but should work on top.

One thing i did read on Jack's site was "The Golden Rules of RV Solar and Electric" was Use high voltage (over 28 volts) on any but the smallest systems (small: under 400 watts) so that is what I am going on as well.

the charge controllers at 30 amps are able to handle 5 total panels if i decide to add a couple more in the future so everything will be sized for 5 panels from roof to batteries.

https://www.solarblvd.com/product_info.php?cPath=1_269&products_id=3047 300 watts of 12 volt panels for $339.00 Add a Tristar 45 amp controller and you will have a good small sized system. Small in the sense of watts, but with some room to expand.

Look at watts; that's how to compare their output. The higher voltage panel will require an MPPT charge controller which is usually more expensive. However, higher voltage panels can have advantages with using smaller wire and simpler wiring connections.
If you're just getting one panel I'd get the 12v panel and a simple PWM charge controller. If you're aiming for a large system go with the less expensive panel on a dollar / watt basis and use a nice MPPT charge controller.

You really need a more expensive MPPT controller to get the most out of the 24v panels.

As you get into the 250 to 500+ watt range the larger panels make more sense IMO.

With MPPT controller you are just looking at physical size and watts. With a PWM controller and 12v panels it is the Isc rating that matters.

Need to post what you want to accomplish with solar.

Westend, those links is too heavy read at this point of the learning curve.

Watts = Volts*Amps.
More watts = more energy harvested.

Further reading material would be useful after this one has been digested, IMO.

You should read this: Golden Rules of Solar

And first, use this Downloadable spreadsheet program to calculate your power use.

You are listing two different types of modules as one is 24V nominal and the other is 12V nominal. Both have intrinsic advantages and disadvantages so power output is not the most pressing decision to make. In the examples given, the crudest estimation of "best" would be power output/$$$ spent.