Solar madness planning stage

[Admin]

I have had a few questions asking how I am planning the installation of the panels on my motorhome.

I am installing:

4 * LG Electronics 320W NeON2
Victron SmartSolar 100A MPPT Solar Charge Controller

First I measured the roof and worked out where all the skylights are. With this installation, I will have three skylights covered by the panels, these are the bedroom, shower cubicle and the toilet. As with the current installation I wanted to make sure that the solar panels do not touch the skylights and that the shower skylight is able to vent. After doing my calculations I was happy that things would fit the way I wanted them to.

Being a belt and braces kind of guy I decided to use an aerial photo of the motorhome roof and virtually install the panels to make sure that it all fitted ok.

I found a video I had of the roof of the van then took a screenshot.





As I know the exact size of the panels already fitted I could measure them and "calibrate" the image to 1 pixel per mm. This meant I could use guides the same size as the new panels to position them.

This allowed me to see where the panels would sit and if the and if the mounting brackets I am using would fit without obstruction.





Next, I found a photo of the actual panels that I am fitting and after formatting it to the correct size I added them to the image.






As you can see they do fit nicely.

The front panel will be mounted using the recycled mounts from the old panel.

The rear panels are going to be mounted on aluminium rails that will run across the width of the roof. These are 50mm (2inch) wide, 150mm (6inch) high and 6.5mm (1/4inch) thick. I know that these are pretty thick and that I could have used 3mm but I am happy with the strength of the 6.5mm angle. There are three sections: 2 x 2032mm long and one which is 1686mm long. They are coloured blue in the image below. This gives a 2875 cm2 footprint on the roof. These sections will be bonded to the roof using sikaflex 512.

The solar panels will be mounted to these rails using 30mm x 30mm x 3mm aluminium angle. There are 2 x 2032mm long and 2 x 1686mm long. They are coloured green in the image below. I am using the 8 panels mounting holes on each panel to bolt them on. I will also be using a dab of sikaflex in each corner and in the center of the mount.

This image shows a side on view from the near side of the vehicle.



Here is the cross section of the panel.




There should be 180mm (approx 7inch) between the roof and the underside of the solar panel.

There will be a video made of the installation and you will be able to watch it on the Motorhomer YouTube channel: https://www.youtube.com/Motorhomer

Make sure you subscribe to the channel and turn on notifications (click the bell) to see the videos.

 

[The laird]

Looks like it’s gonna be a work of art mate ,looking forward to the videos as well

 

[wildebus]

Looks good. Are you only securing the rails to the roof with Sikaflex? I'd feel a mite nervous myself with that large area as a bit of a wind channel driving down the motorway and the potential lift that could happen.
(I used VHB on my rails but still felt I needed mechanical fastenings - maybe a bit too old-school but didn't feel 100% comfortable without them)

 

[Admin]

Looks good. Are you only securing the rails to the roof with Sikaflex? I'd feel a mite nervous myself with that large area as a bit of a wind channel driving down the motorway and the potential lift that could happen.
(I used VHB on my rails but still felt I needed mechanical fastenings - maybe a bit too old-school but didn't feel 100% comfortable without them)

With 5300 cm2 of bonded surface area I would think you could lift the van off the floor.

 

[saxonborg]

Added bonus is with so much of the roof area covered by the panels the roof shouldn’t get as hot in the summer and the interior of the moho might be tad cooler. You will remember Landrover used to fit a Safari roof to their export models to give the same effect.

 

[time4t]

Have you thought about tree branches getting caught underneath Phil.

I'll be fitting spoilers on the leading edges & closing off the sides with ally angle that has holes drilled in it to aid ventilation, which will create a vacuum under the panels helping to hold them on.

Phill

Ps., I thoroughly agree with your choice of ally angle, it's the same thickness as mine!

 

[saxonborg]

With 5300 cm2 of bonded surface area I would think you could lift the van off the floor.

If I remember correctly the fire engine manufacturers I used to work for bonded a 300 x 300mm square plate with lifting eye to the roof of a GRP fire engine body using only Sikaflex, so I would be quite happy with your installation.

 

[Trek]

I wouldn’t want to cover my roof skylights ! (Or do you have air con in the habitation area ?)

If it was mine i would fit three panels to the roof and consider only using the fourth panel when your pitched up somewhere

storing the fourth in the m/h garage and rigging up a set of flying leads and possibly a frame to sit the panel at an angle so when on a site and you need the extra charge you could place the panel on the ground pointing at the sun
(Padlocked for security ?)

Possibly it would produce more as it is could be set at a better angle to catch the sun than being flat on the roof though would need adjusting to follow the sun ?

Saying that i only have a single 100w panel at that does me ok with two varta LFD90 leisure batteries

 

[Admin]

After doing a few calculations I am reducing the aluminium angle from a 100mm base to a 50mm base. This still leaves a 2875 cm2 footprint on the van.

I am going to add three extra supports on the back panels, these will be on the outer sides and in the middle where the panels meet.