Interesting Idea for solar wings

[freds]

One of the YouTube channels that I occasionally watch show re-enforcing solar panels to have them become popup wings on the side of the vehicle.

https://www.youtube.com/watch?v=lcck1ejlXt8


I am considering this as I have a very large blank surface area on the side of my rig where the kitchen and the bath room is.


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[windtrader]

Fred,I've seen several methods of increasing panel array once a roof is full. One is stacking and sliding. It requires more hardware but some designs are rather minimal ,especially if involving some manual intervention rather than total push button remote. It could be designed to slide out on either side

A fold up design is an easy design. Basically a hinge with a couple struts. Simple and effective. Mounted on one side may limit parking orientation of bus in certain locations. The simplest design would just swing up, meaning the panel is exposed to the outside and subject to damage as well as being unusual and unsightly to some. You could add a thin lightweight yet stiff cover while on the road, then unfasten and roll up while in use.
I'm not there yet, as in needing more generation than what I can fit on top but I have thought about increasing capacity. One other option is tilting existing roof panels to increase efficiency. I've not done any research to run the numbers but depending on the increased capacity that might work. More hardware involved.

Last option, one I have utilized before, being too lazy to install new panels up top, is to carry them unmounted then set them up when I need them on the ground along with wiring back to the controller. This has worked very well, especially in places where I catch shade some part of the day and the outboard panels p;ump all day long. This works for occasional added power. I wouldn't do this if that was needed all the time.

[dtcerrato]

There was a bus at the last couple of Nappanee rallys that had actuators to pitch the panel array towards the sun so I guess that's also an option to get more juice from the array. 10 panels with good sun angle opposed to 20 fixed. Just saying...

[epretot]

10 panels with good sun angle opposed to 20 fixed. Just saying...

What is the efficiency difference of angle over flat assuming all other factors were equal?

I would like to modify my panel mounting brackets in the future to angle. However, automation is further than I'm willing to go.

I'm willing to manually position them as I won't be moving the bus for weeks at a time.

[dtcerrato]

I can't personally answer the aim vs fixed answer with any particular knowledge but have a feel for experiencing the differences of our fixed roof panels during early & late day sun (low in the sky) to high noon sun. Quite the difference in wattage coming to the charge controller. Most large solar farms the arrays follow the sun in the arc of a day. Most adjustable panels I see are manually operated. The actuators I see are also manually operated. The large array of solar farms I would assume are automatic and autonomous.

[oltrunt]

Quite a bit of hardware but the electric linear actuators I use to tilt the top of my bus work great.  I did have to reinforce the base plate on the actuators as they were plastic and not up to snuff.  Once that was done I've had no trouble with them.  Jack

During design:
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Finished:
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[freds]

What is the efficiency difference of angle over flat assuming all other factors were equal?

I would like to modify my panel mounting brackets in the future to angle. However, automation is further than I'm willing to go.

I'm willing to manually position them as I won't be moving the bus for weeks at a time.

The efficiency varies by latitude and time of the year. At my location it would be 32 ° in June, in November where we are right now it is 64 °. So my flat mounted panels are probably producing 25% less power..

[Glennman]

I know the guy that has a Youtube channel called "Beginning From This Morning" has quite an elaborate actuator solar panel extension system. He's probably the one you saw at the bus rally. As I reflect back to my 3000 watts (soon to be 3600 when I add two more panels to the front roof area), I can see where I could have been much more careful with my design and I could have gotten over 4000 watts easy. I have a 10" wide path all the way down the middle of the roof that I can walk on for maintenance, but it is definitely wasted space from an efficiency standpoint. I bought 4 panels early on that I ended up designing around, instead of designing the system before buying any. You know how it is when the "right deal" comes along before you're ready! At any rate, I have found the system being flat and fixed in place to be quite adequate, especially when I add the 2 additional panels.

[windtrader]

I was bored so figured I'd answer the question about power output of panels when laying flat vs facing the sun. Surprised me a lot. Not a scientific experiment but now merits more research and testing. If in fact, the difference is like what I recorded, orienting mechanisms may very well be worth the effort vs more panels.
flat 5.0 ampstilted 8.65 amps
70% more current when tilted.

As Fred states, it depends on angle of sun. If sun is direct above, there is little difference with a couple degrees of tilt. The test was done around 12:30pm, Sacramento 38.5 lattitude, sun angle?

[luvrbus]

I see people on top of buses cleaning the panels and have ropes to turn the panels to get a few more watts ,a starter button works for me it is easier. Here in the valley we are getting solar farms everywhere the green hay fields are disappearing, and panels are covering the fields making for more dust it sucks.With the snowbirds flocking here seldom do drive on  hiway 95 that you don't see people on the side of the road picking up panels that have blew off 

[epretot]

flat 5.0 ampstilted 8.65 amps
70% more current when tilted.

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Wow I didn't expect that.

Because the parking position of the bus is unpredictable, the bracket modification has to allow for an angle adjustment in all directions.

Should be fun...

[dtcerrato]

In Alaska summertime solar panels are nearly vertical and also TV dishes are looking at the very low horizontal horizon. Looks kinda funky but a requirement at the high latitude. With that being said our fixed flat solar on the bus in AK summer is only picking up maybe 30% of its rated capacity while in the FL summer sun at high noon it's cranking what's on the spec plate.

[windtrader]

.With the snowbirds flocking here seldom do drive on  hiway 95 that you don't see people on the side of the road picking up panels that have blew off

LOL, don't mention highway 95, Interstate 5 can seeing flying panels crashing onto the roadway too.

[windtrader]

In Alaska summertime solar panels are nearly vertical and also TV dishes are looking at the very low horizontal horizon. Looks kinda funky but a requirement at the high latitude. With that being said our fixed flat solar on the bus in AK summer is only picking up maybe 30% of its rated capacity while in the FL summer sun at high noon it's cranking what's on the spec plate.

Yeah, I think there is something to the large difference in output based on orientation. I'm always learning, someone will come along and say yeah you dumbass, don't you know that. well, no i don't thank you very much and kiss my @$#.

[Iceni John]

This article convinced me to make my panels tiltable:  https://www.solarpaneltilt.com/
This website told me how much power to expect at different locations:  https://pvwatts.nrel.gov/

I made a central walkway on my bus roof between the two roof hatches, and my eight panels (two rows of four) are hinged to it.   They usually lay down against the roof for travel at 21 degrees down, but they can be manually tilted up for better insolation in the winter or at higher latitudes:  I can raise them to flat level, or to 21, 33 or 45 degrees up.   In the summer I probably won't need to raise them at all, but in the winter when every photon is precious I will raise the panels on the side opposite to the sun.   Obviously the sun-side row of panels are at 21 degrees down all the time, but having half the panels tiltable is better than tilting none of them at all.   When stowed down and locked against the roof for travel they make no wind noise at all, and when raised fully up they can easily withstand the strongest gusts of desert wind.   If the two rows of panels are at different angles each row will obviously be producing slightly different power than its neighbour, so partially for this reason I have each set of four panels running through its own fused combiner box that sends their power down 4AWG cables to a 50A breaker and then to its own Morningstar TS-MPPT-60 charge controller;  each CC then charges its own bank of batteries, and each battery bank's output runs through a 250A Schottky diode before both outputs are combined at the main DC busbar.   This prevents one battery bank backfeeding into the other:  I have two entirely separate PV and battery systems running in parallel.   Redundancy is good!

Under the roof walkway I have two quick-connect water outlets, so to wash down the panels I only need to take a washdown brush with a short curly hose up to the roof, then I plug it in to either of the water outlets to easily and safely keep all the panels clean.   Even small amounts of dust/leaves/birdshit/etc can significantly reduce panels' outputs, so keeping them clean is important.

I think that the amount of power the panels can produce under less-than-ideal conditions is more important than merely covering the roof with as many panels as will fit, especially when those panels are not capable of ideal solar harvest.   It really wasn't too difficult to make an effective single-axis tilting system, and I think I'll appreciate it if/when boondocking in the winter.

So far, so good.

John