Needing opinions on solar panel mounting on "C" sloped nose.

[glennts]

Recently switched out (3)130w,12v flat mount roof panels for (3)320w, 24v panels and would like to mount a 4th panel on the slope of the nose to catch early morning light. That surface has some flex so I'm not confident there is much plywood under there to just screw mount Z brackets. Another consideration is if the gap under the panel from Z brackets would introduce any lifting air pressure issues while driving. My guess is the air flow after the nose would rise up over the panel much like on an airplane wing.

So as an alternative I'm considering 3M VHB which others have reported success with in roof mounts and use it to secure full length angle mounts or, if I allow for a wire path, VHB the panel directly to the nose surface. This second approach then brings up the heat buildup issue.

A third approach would be to glue mount 1/2" ply that is slightly larger than the panel dimensions directly to the nose to beef up the fiberglass surface and use screw mounted Z brackets for the panel. I'm doing an RV re-paint and will fair the plywood edges with epoxy resin so aesthetically it should look OK.

[pianotuna]

glennts wrote:

pianotuna >> I would use the 4th panel as an awning.

An interesting solution worth considering however sudden wind gusts in the mountains can peak > 50 mph in the blink of an eye and that might be a problem.

Then overbuild the mounting by using angle aluminum and seriously strong metal "props".

Or have the same sort of system that some electric awnings have-where they close using an actuator during wind gusts.

My first battery bank was 875 amp-hours @ 12.6 volts. That gave me 5500 watt-hours usable. My next one will be 700 amp-hours of SiO2 which yields 7000 watt-hours usable and in extremis 8800 watt-hours.

So consider adding another LI battery to the mix.

[glennts]

Thank you for the responses.

Lwiddis >>960 solar watts isn’t enough?

The panels are feeding a 200a, 24v Lipo4 bank and power the Norcold, a microwave, 2 laptops and 2 external monitors for about 12 hrs/day and occasionally the AC or elec. heater. On full sun days there is no problem with the load but on full cloudy days more capacity is needed. A 320w 24v panel is @ $200 so why not find a way to make it work... there's no more room on the roof.

BFL13 >>I had a panel on the C's roof up front just back from the front cap and almost lost it from wind effect while driving.

For 12 yrs the 3 12v panels flat roof mounted with Z brackets using 1 1/2" roofing screws had no problems. These new 24v panels are considerably larger and even with two mounted just back from the front edge they are fine.

rockylarson >> I would not go with a design that locked me into always parking in a particular direction to function.

The 3 flat roof mounted panels are going to do what they do regardless of orientation. If a nose mount would work for a 4th panel then pointing East, West and especially South would provide some extra advantage.... at least that's my thinking.

I spend May - Oct at 8,200' in the Rockies and have 360deg unobstructed horizon views so no issues there. The rest of the year is usually spent beaching on the Texas Coast which is why I want to squeeze more out of the low Winter sun.

pianotuna >> I would use the 4th panel as an awning.

An interesting solution worth considering however sudden wind gusts in the mountains can peak > 50 mph in the blink of an eye and that might be a problem.

[pianotuna]

I would use the 4th panel as an awning.

Front cap may not be a wise place to put such a device.

[FlashBuddy]

IDK - Was thinking of making or purchasing portable solar suitcase to chase early and late sun angles?

[Yosemite_Sam1]

rockylarson wrote:
I would not go with a design that locked me into always parking in a particular direction to function. Too many variables in views, site design, satellite access, etc.

Indeed, CW offered to mount it on the roof and I said, I want to just orient it whenever the optimum sunlight is.

Never regretted it.

[rockylarson]

I would not go with a design that locked me into always parking in a particular direction to function. Too many variables in views, site design, satellite access, etc.

[BFL13]

I had a panel on the C's roof up front just back from the front cap and almost lost it from wind effect while driving. It wasn't mounted as well as it should have been but it did go to show how strong the pressure is there.

(I heard it hammering, and was able to pull over in time--lucky!)

Our front cap is fibreglass or whatever it is, and the roof is rubber on wood, so not the same for mounting things. I would not try that with our front cap.

Perhaps you could get the same thing for the morning low sun by rigging the front roof panel so it can tilt. There have been posts showing how guys have done that with roof mounts.

[Lwiddis]

960 solar watts isn’t enough? As an amateur I wouldn't guess at airflow.