400 watts on my truck bed cap

[TouringDan]

Last summer I decided to venture into the solar world by getting two 100 watt panels, an MPPT controller and some wire (see Touringdan's simple portable 200 watt solar system dated 7/14/18). It all went well, so I decided that I would install some permanent solar on our 66 Tradewind. I read some comments about installing permanent solar on a vintage trailer that it just wasn't the right thing to do. I mulled over the appearance aspect. At the same time I had installed a 12v compressor fridge in the truck that requires about 30-40 Ah of battery power per day. Most folks with a compressor fridge have installed a dedicated battery and a solar panel on their truck to keep the battery charged. I had not done this yet and was relying on the truck battery to keep the fridge going. This was all fine when the truck was running, but then when I turned the truck off, the fridge started to heat up. The problem of inadequate power for the fridge and the appearance of 4-100 watt solar panels on our beautiful vintage 66 Tradewind led to the thought of installing the 400 watts of solar on the truck bed cap.



I had already purchased the 4- 100 watt panels. I went with the compact monochrystaline panels from Renogy. These panels are considerably smaller (21%) than the Grape panels I bought for permanent solar last summer. This allowed me to install 400 watts of solar. If I had gone with the Grape panels I would only have been able to install 300 watts in about the same area. The following photo shows the comparison of the panels.I bolted the panels together at two locations and installed six supports on each side. The supports were 2" deep which was required due to the crown on top of the bed cap. There was about a 6 degree slope on the bed cap roof where the supports were installed. I had to bend each support to provide the proper contact with the roof for the VHB tape to work properly. Here are photos of the before bending and after bending.
I watched a UTube video by Will Prowse about using VHB tape and having a safety backup. I agree completely, so the front two supports will be bolted. Here is a photo of the completed 400 watt solar assembly and of one of the front assembled supports that will also be bolted.

I gave a lot of thought to connecting the panels in series-parallel or straight parallel. I was going to make all the connections on top of the bed cap, but then I realized that I could penetrate the cap with all 8 wires and make the connections under the ceiling of the bed cap. This way I could change from parallel to series-parallel if I wanted to. I decided to go with parallel because supposedly that is how Lester and AM Solar do theirs. I also had two four to one branch connectors that I wanted to utilize completely.

I got eight grommets to make water tight penetrations. I trimmed the bottom to accommodate the thick bed cap roof and sealed the installation with Trempro 635. Here are photos.

Dan

[TouringDan]

Correction- portable instead of permanent in the second paragraph.

Correction- Lewster instead of Lester in the next to last paragraph.

I think it is important to emphasize the compactness and how narrow the Renogy panels are. This makes them especially appropriate to use on an Airstream with the curved roof.

I had to wait for a friend to come over this evening to lift the 400 watt solar panel assembly onto the top of the bed cap. It all looks good. I will finish the installation tomorrow, take photos, do a test drive and test the solar performance.

Dan

[wulfraat]

Following! Great idea!

[TouringDan]

I finally finished installing the 400 watt solar assembly today. The front two Z brackets are bolted and secured with VHB tape. The rest of the Z brackets only have VHB tape. It drives fine and I am confident that the panels are quite secure.

Please don’t hesitate to comment or ask questions. That is what this forum is all about.

Dan

[wulfraat]

Very great idea. Looks awesome, very clean install. Lots of power generation up there!

[TouringDan]

Thanks wulfraat. I could also install 200 watts on the truck cab if I needed to. However, I believe 400 watts will be plenty for our style of camping and we usually camp with a kayak on the truck cab.

Dan

[Piggy Bank]

Looks like it came that way. Great job.

[TouringDan]

Thanks Piggy Bank. While I don’t ever plan on removing the 400 watt solar assembly, individual panels can be replaced as needed by unbolting from the adjacent panel and from the Z brackets.

Dan

[AirMiles]

Very nice way to increase solar arrays for those with limited roof space.

[gandttimes]

When I saw the first picture of the truck cap I thought " how'd a picture of my truck get in there".
I did this setup 4 years ago but I first used renogy flexible panels and as was with everyone else, they went south on me about 18 months later. Renogy was kind enough to stick by a warranty and refunded everything.
I waited until I could get the smaller panels as you have and installed 3 of them in 2017 using a 25 ft 6ga umbilical to connect to the trailer where the end Pico connector comes out from near my battery box.
I initially set this up because most of our camping is done up here in the northwest where the tree canopy makes parking the trailer in a sunny enough spot for solar,challenging. This year I added a Renogy 100w suitcase with a Y connector and 20 ft of 10 ga to insert between the connector from the truck and the trailer lead when I need something more directional in really heavy tree cover.
Tried it all out for a week last monthe and it all worked perfectly.

[Re-Pete]

Nice Job Dan! Looks great.

[TouringDan]

Originally Posted by gandttimes

When I saw the first picture of the truck cap I thought " how'd a picture of my truck get in there".
I did this setup 4 years ago but I first used renogy flexible panels and as was with everyone else, they went south on me about 18 months later. Renogy was kind enough to stick by a warranty and refunded everything.
I waited until I could get the smaller panels as you have and installed 3 of them in 2017 using a 25 ft 6ga umbilical to connect to the trailer where the end Pico connector comes out from near my battery box.
I initially set this up because most of our camping is done up here in the northwest where the tree canopy makes parking the trailer in a sunny enough spot for solar,challenging. This year I added a Renogy 100w suitcase with a Y connector and 20 ft of 10 ga to insert between the connector from the truck and the trailer lead when I need something more directional in really heavy tree cover.
Tried it all out for a week last monthe and it all worked perfectly.

The bottom line is providing the solar needed to recharge your batteries based on your electrical consumption. I think that I will be fine. But if not, I can always add a couple of portable panels. My solar controller will handle up to 700 watts.

I would like to see a photo of your truck with solar panels on the bed cap.

Dan

[TouringDan]

I have 400 watts solar with all the panels connected in parallel. These feed into the Victron 100/50 solar controller (see photo).

I could have gone with a 100/30 solar controller, but this way I will be able to add up to 300 more watts of solar and the controller will be large enough.

The output from the solar controller can either charge the deep cycle flooded 27DC battery powering the fridge (see photos)
or connect to the mc-4 connectors at the Airstream A frame and charge the two BB 100 Ah lithium batteries (see photos)
The biggest problem when switching from charging lead acid batteries to charging lithium batteries is that I have to change the charging profile of the controller.

Dan

[gandttimes]

Dan, as requested. Pictures of my panels.
Note the similar color of truck which got my attention in the first place. Your cap roof certainly looks a lot neater than mine but the leads through the roof were already there to the female receptacle on the bumper from the failed flexible panels so I decided not to reroute.
The 3 100w panels, plugin for the 6ga welding cable umbilical, the 25 ft umbilical, and the waterproof connector coming from my Bogart Engineering SC-2030 mounted inside as close to the batteries ( 2 6v Crown 235) monitored by a TM 2030.
Not shown is a Y connector which connects between the two waterproof Pico connectors and has a 25 ft lead to the 100W Renogy suitcase which is more directional when we are under more cover and need an extra boost.

[gandttimes]

Don't know why it sends two copies of everything.

[Mollysdad]

That's a brilliant idea. I'm surprised more folks don't do that. Saves drilling in the AS roof and you can park the truck in the Sun and the trailer in the shade.

My only question is why the batteries are in the truck and not the Airstream?

[gandttimes]

Originally Posted by Mollysdad

That's a brilliant idea. I'm surprised more folks don't do that. Saves drilling in the AS roof and you can park the truck in the Sun and the trailer in the shade.

My only question is why the batteries are in the truck and not the Airstream?

Don't know about Dan, but mine are in my trailer.
George

[WhereStream]

Looks pro.

The VHB tape, how much wiggle room do you have when using it?

Does it set up immediately, or can you move it around?

[TouringDan]

Originally Posted by gandttimes

Dan, as requested. Pictures of my panels.
Note the similar color of truck which got my attention in the first place. Your cap roof certainly looks a lot neater than mine but the leads through the roof were already there to the female receptacle on the bumper from the failed flexible panels so I decided not to reroute.
The 3 100w panels, plugin for the 6ga welding cable umbilical, the 25 ft umbilical, and the waterproof connector coming from my Bogart Engineering SC-2030 mounted inside as close to the batteries ( 2 6v Crown 235) monitored by a TM 2030.
Not shown is a Y connector which connects between the two waterproof Pico connectors and has a 25 ft lead to the 100W Renogy suitcase which is more directional when we are under more cover and need an extra boost.
Attachment 346992Attachment 346993Attachment 346994Attachment 346995

gandttimes

All I can say is that great minds think alike. You were the first though. I like what you have done. Our designs are incredibly similar. I can charge up my trailer lithium batteries by connecting a 10 ft umbilical cord from the truck to a 20 ft long #10 welding wire from the A frame to the lithium batteries. I don’t plan on carrying any extra portable panels for now but if I do, I would probably connect them to leads I have in the rear of the trailer feeding the Victron 100/15 controller in the Airstream (see photos). Of course, if I wanted to go nuts I could add 300 watts portable to the truck controller and 200 watts portable to the Airstream controller.

Dan

[TouringDan]

Originally Posted by Mollysdad

That's a brilliant idea. I'm surprised more folks don't do that. Saves drilling in the AS roof and you can park the truck in the Sun and the trailer in the shade.



My only question is why the batteries are in the truck and not the Airstream?

Mollysdad

I agree. I am surprised that more folks don’t do this.

I have one flooded battery in the truck for the compressor fridge and 200 Ah of lithium in the trailer. I can charge either bank from the truck controller, just not at the same time.

Dan