DIY solar suitcase

[Tom&Shelly]

I was just watching a video on robot dogs and it occurs to me that if we got one, strapped the solar panel to her back (I assume female robot dogs are better behaved than male robot dogs) we could have her wander around camp all day looking for holes between the trees to gather sunlight.

Of course, we would need another robot dog to take with us hiking....

Tom

[tony.latham]

video on robot dogs

You obviously haven't smelled robot dog doo.

Tony

[featherliteCT1]

bdosborne,

Thanks for the feedback about your Cerbo GX successfully operating in low temperatures. Good for me to know.

Similar to Lfhoward, I lug around four 100W DIY "portable" panels utilizing glass panels with aluminum frames. They weigh about 20lb each and are cumbersome to haul around. IMHO, some of the lightweight portable panels are a great product for boondockers due to easier storage and being relatively light weight. As I get older and older, the price and quality differential becomes more and more insignificant to me.

[bdosborn]

Of course, we would need another robot dog to take with us hiking....

I always wanted a pack lama, I wonder how much they poo? You think the neighbors would mind a lama in our backyard?
Bruce

[Tom&Shelly]

video on robot dogs

You obviously haven't smelled robot dog doo.

Tony

Right! We'll also need a robot human to walk around with a bag and pooper-scooper...

Tom

[Tom&Shelly]

Of course, we would need another robot dog to take with us hiking....

I always wanted a pack lama, I wonder how much they poo? You think the neighbors would mind a lama in our backyard?
Bruce

Depends how big the back yard is. Ours have alpacas, but they're over the ridge about a half mile away.

Tom

[lfhoward]

Lfhoward,

I am glad to see that you posted data showing that your Rpi operates in 28.8F temperatures.

My Rpi connects to a Netgear router where the router serves as a LAN (with no www Internet available). Both devices are located inside my trailer.

When temperatures get below 35F, my Victron Connect app has a hard time connecting to the devices. Below 30F, the connectivity is erratic. Below 20F, the devices are not reliable at all and will not stay connected.

Both devices have published operating specs with a lower temperature range of 30F.

Until you posted your data, I could not tell which device was causing the problem or if both devices were causing the problem.

I now think that the Netgear router has been the limiting device.

Regardless, I solved the problem by putting both devices in my insulated battery box wherein my batteries reside. When ambient temperatures are around 30F, the heat generated internally by the devices in the box keeps the devices at 50F. So far, the devices have been running fine, with temperatures consistently about 20F higher than ambient temperatures.

Last week the ambient lows were about 0F, before I located the devices in the box. This week, since I located the devices in the box, the ambient lows have only been about 30F. So far so good. I am curious what the temperature differential will be in extremely cold ambient temperatures.

Normally, I do not look forward to colder temperatures. But, the science must continue!

That’s interesting about the Bluetooth not connecting in cold weather. I have never had a problem with that. You could try adding a USB Bluetooth dongle to the Pi, which could take over the job from the Pi’s radio and let it concentrate completely on WiFi. I got this one from TP Link and it works great (no drivers to install). You can turn off the Pi’s native Bluetooth on the Victron menu afterwards.

https://a.co/d/1kcW6sd

Speaking of malfunctioning at cold temperatures, I had tons of issues with my peripherals dropping out below freezing when I used homemade communication cables like these. I don’t recommend trying to save money in this way, for anyone else reading this.



These were like the ones Andy made for the Off Grid Garage and they worked for him because it never gets that cold in sunny hot Australia.

It is worth buying the Victron branded VE.Direct communication cables. I have had zero issues at low temperatures since I did.

https://a.co/d/1iuOy2C

[featherliteCT1]

You could try adding a USB Bluetooth dongle to the Pi,

Thanks, I will look into that.

I used homemade communication cables

Me too. Then I switched to the $30 OEM Victron cables ... I needed four of them. But they made no difference. Still, I am glad I switched because I have read that the home made cables can cause other problems because they are "non isolated" (whatever that means).

Also, I have developed OCD due to frequent looking at the Cerbo GX Rpi screen to see if it is still working.

[lfhoward]

Tonight I put the finishing touches on my DIY solar suitcase.

I had previously found two 100 watt Renogy panels for very little money, and hinged them together and made stands out of window casement hinges and aluminum angle.





Today I installed a spring loaded handle and some latches to hold the suitcase closed. I used circular felt stickers meant for the bottom of chair legs as bumpers to pad the suitcase when it's closed, and to provide resistance for the latches.



Close-ups of the hardware:







So far this is working well. I have two more latches I could put on it if the two I have are not sufficient to keep it closed. I also have a felt case on the way from Amazon so that the panels don't get scratched while stowed under the bed.



Link to the case on Amazon: https://a.co/d/03v2dYd

[featherliteCT1]

Your portable panel rigging looks great!

[bdosborn]

Boy, that turned out nice. Well done....
Bruce

[lfhoward]

Thanks Featherlite and Bruce!

It turns out I found another pair of identical panels, so I scooped them up and now I will be building a second 200 watt suitcase. That will give me a 400 watt ground array. With all four panels being the same, there will be no losses due to combining different voltages and amperages.

Once I have the second one built, I will have two Renogy Eclipse 100 watt suitcase units for sale, like these:

Renogy 100 Watt 12 Volt Portable Solar Panel with Waterproof 20A Charger Controller, Foldable 100W Solar Suitcase with Adjustable Kickstand, Solar Charger for Camping RV Off Grid System Power Station.
https://a.co/d/d6svfI7



One suitcase has a built in pwm charger, and the other one does not. They can be run in parallel to feed the charger, or, as I did, put in series and run through a more efficient mppt charge controller instead of the Renogy pwm unit.

These come with hard protective cases and they are downright awesome when it comes to efficiency. I have gotten more than the rated 100 watts from each in full sun using my Victron mppt charge controller. They are in pristine condition.

If anyone is interested in rehoming these 100 watt suitcase panels, I am in the Philadelphia area. SE PA, south NJ, and DE are all close enough to meet up. I am thinking $250 each. Amazon has them priced at $350.

[tony.latham]

so I scooped them up and now I will be building a second 200 watt suitcase.

Good grief. You'll put the sun out!! Suck it dry! We're all gonna die!

Tony

[lfhoward]

so I scooped them up and now I will be building a second 200 watt suitcase.

Good grief. You'll put the sun out!! Suck it dry! We're all gonna die!

Tony

Sounds like something a Star Wars villain would try to do!

[tony.latham]

Sounds like something a Star Wars villain would try to do!

We're trying to suck it dry behind the shop.





Tony