My Green & Yellow Wagon build (DONE)

[penrow]

I am building a solar generator, in a wagon with a 200 watt panel attached. I got the idea from this thread:
https://diysolarforum.com/threads/upgraded-my-mobile-solar-generator.35612/#post-516735
Along with the solar panel it will have 2 200 amp hr Ampertime batteries with 200 amp BMS (parallel) and a volt works 2000 watt Inverter. I hope to get my batteries this week and have it done by next weekend, I'll add more pics when finished. I added 5/8" plywood to the bed of wagon and painted to match, changed the air tires for these solid rubber wheels, painted solar mount and trim around solar panel. I started to paint the back of the panel which was a disaster and I hope it didn't damage it, but it looked so bad I had to cover with 1/4" plywood. I just hope it rolls well with the 2 batteries installed and the width of the wagon is small enough I can fit it through a normal 36" doorway.

 

[sunshine_eggo]

I am building a solar generator, in a wagon with a 200 watt panel attached. I got the idea from this thread:
https://diysolarforum.com/threads/upgraded-my-mobile-solar-generator.35612/#post-516735
Along with the solar panel it will have 2 200 amp hr Ampertime batteries with 200 amp BMS (parallel) and a volt works 2000 watt Inverter.

Very little solar to charge that much battery. You'll probably get about 1kWh/day in great sun, but you have 5.1kWh battery.

I hope to get my batteries this week and have it done by next weekend, I'll add more pics when finished. I added 5/8" plywood to the bed of wagon and painted to match, changed the air tires for these solid rubber wheels, painted solar mount and trim around solar panel. I started to paint the back of the panel which was a disaster and I hope it didn't damage it, but it looked so bad I had to cover with 1/4" plywood.

Sorry. You've ruined the panel. Start over. The backside of panels should be unaltered as it's critically important for shedding heat. Cells get very hot, and their performance degrades with elevated temperature. They radiate off the back to keep temperature manageable. Removing the plywood might make it workable, but don't be surprised if your PV performance is poor.

Aside from that, it looks pretty cool.

 

[penrow]

Very little solar to charge that much battery. You'll probably get about 1kWh/day in great sun, but you have 5.1kWh battery.



Sorry. You've ruined the panel. Start over. The backside of panels should be unaltered as it's critically important for shedding heat. Cells get very hot, and their performance degrades with elevated temperature. They radiate off the back to keep temperature manageable. Removing the plywood might make it workable, but don't be surprised if your PV performance is poor.

Aside from that, it looks pretty cool.

Thanks bud for the feedback! I have 3 more solar panels I can hook to it but they are small 100 watt panels. I plan on getting a few more larger ones. The panel with the paint, I have to keep it until it dies, I'm so indebted to Amazon I'm not buying anything else for at least for 6 months. I will drill some holes at top and bottom to allow for some ventilation. I really appreciate feedback from someone who "KNOWS"
I would like to ask you this, my battery recommended 2 x (6 AWG cables) to connect in parallel what is that equivalent to in a single cable? I also wanted to let everyone know that when I painted the back of the panel, the paint absorbed into it like a sponge. 90 % of the paint absorbed after I painted it dark green, it looked real light like a pastel green. I don't know what its made of but don't paint it. I thought I ruined it because of that not even considering the heat aspect of it. I tested it out today hooking it up to my milk crate solar generator while mostly overcast and it hit 150 watts, but heat wasn't a factor. Maybe its tough as a timex watch and will take licking and keep on ticking. I make mistakes but learn from them and hopefully others can learn from mine also, This really is a great forum Will put together with a wealth of knowledge and helpful members.

 

[sunshine_eggo]

Thanks bud for the feedback! I have 3 more solar panels I can hook to it but they are small 100 watt panels. I plan on getting a few more larger ones. The panel with the paint, I have to keep it until it dies, I'm so indebted to Amazon I'm not buying anything else for at least for 6 months. I will drill some holes at top and bottom to allow for some ventilation.

I would completely remove the plywood.

I really appreciate feedback from someone who "KNOWS"

Please check my signature for the value of my advice.

I would like to ask you this, my battery recommended 2 x (6 AWG cables) to connect in parallel what is that equivalent to in a single cable?

Doubling up on a gauge roughly drops it by 3, so 2X 6awg is a single 3awg.

Given your 2000W inverter, 2000W/12V/.85 = 196A

That's going to require some beefy cables. I'd be looking at 2 awg (or heavier) welding cable for interconnects and main cables.

 

[sunshine_eggo]

That's going to require some beefy cables. I'd be looking at 2 awg (or heavier) welding cable for interconnects and main cables.

Also worth noting that while those cables can handle the ~200A current, it may not be a favorable voltage drop. If your inverter sees a 2V drop between rest and max load, it's going to shut off prematurely. 1/0 or 2/0 may be the better choice.

https://www.calculator.net/voltage-drop-calculator.html "Estimated Resistance" tab.

Any voltage drop below 3% is to code and is generally acceptable.

Looks like at up to 5' one way cable run, 2awg will give 2.6% drop:

Voltage Drop Calculator

This free voltage drop calculator estimates the voltage drop of an electrical circuit based on the wire size, distance, and anticipated load current.

www.calculator.net

 

[Maitake]

Why do I like this wagon so much?
Does it have a name?

 

[penrow]

Why do I like this wagon so much?
Does it have a name?

Ha Ha! Not yet. My wife was calling it " a waste of money" but I like it. I feel better knowing if something happens ( besides an EMP attack) I should have enough electricity to not be in the dark and be able to run some small appliances. I was on vacation this week and had some time , grabbed a couple cans of spray paint and had fun. I ordered the solid rubber wheels and they had the yellow rims, the wagon already had one spot of yellow on it by the handle and that set the color scheme

 

[penrow]

Also worth noting that while those cables can handle the ~200A current, it may not be a favorable voltage drop. If your inverter sees a 2V drop between rest and max load, it's going to shut off prematurely. 1/0 or 2/0 may be the better choice.

https://www.calculator.net/voltage-drop-calculator.html "Estimated Resistance" tab.

Any voltage drop below 3% is to code and is generally acceptable.

Looks like at up to 5' one way cable run, 2awg will give 2.6% drop:

Voltage Drop Calculator

This free voltage drop calculator estimates the voltage drop of an electrical circuit based on the wire size, distance, and anticipated load current.

www.calculator.net

Thanks again for the advice! I plan on going with 1/0 AWG wire as the longest run even possible in this set up would be 20" to inverter, battery connections in parallel would be 12" max. The inverter is rated at 90% efficiency, I noticed in your formula above you assumed 85% so I presume that will lean in favor of the 1/0 instead of 2/0 and the cable lengths being so short. Is my thinking right? I really appreciate your input.

 

[penrow]

Very little solar to charge that much battery. You'll probably get about 1kWh/day in great sun, but you have 5.1kWh battery.



Sorry. You've ruined the panel. Start over. The backside of panels should be unaltered as it's critically important for shedding heat. Cells get very hot, and their performance degrades with elevated temperature. They radiate off the back to keep temperature manageable. Removing the plywood might make it workable, but don't be surprised if your PV performance is poor.

Aside from that, it looks pretty cool.

I think you are right, today I could never get above 150 watts in the summer sun in Georgia. I am getting another panel for the wagon and keeping the other one because it still works just not to its full potential , and I will not be painting it (well maybe just the frame , just because I still have paint left) I'm not living off grid or anything just want some peace of mind , I plan on getting a dc powered fridge or cooler and some electric blankets and I'll be good. As for the batteries, this set up may only be temporary . My dad just bought a camper van/RV and may put one of the batteries there . Good thing is I have 10 yrs to utilize , move or whatever.

 

[penrow]

It is done! replaced the other panel with a 200 watt newpowa. I just now got to test it ( although partly cloudy and after 4pm it already outperforms the one I painted that was from Bougerv) I hit 165 watts without even adjusting the angle and I am happy. Midday and tweaking the angle I know it will bring in 180 watts or right there at it. Pics attached. Also have a storage area underneath inverter for cables or spare fuses, phone charger cables or whatever. I ordered 3 of the Newpowa panels , so I have 2 more I can connect as satellite panels if needed. My HOA doesn't allow roof mount panels or ground mount systems, so I am just doing what I can to have a little electricity in case of emergency, I also like learning and when I retire I may opt for a little cabin off grid somewhere and be able to put a little system together.

 

[sunshine_eggo]

Happy to see that sexy white panel backing...

 

[penrow]

Happy to see that sexy white panel backing...

Thanks for the advice and suggestions, I appreciate it.

 

[penrow]

Just wanted to say, I'm thrilled with my solar panel. It is performing very well. I was hoping to get 180 watts, so 191 is Great!

 

[Electrobob]

Super nice build, congrats! I think the cart system works great. It allows for a lot of on board power that dwarfs what could be had from the pre-built store bought units. Love the idea of the solar panel so the whole thing is a single self contained unit. Nice color scheme.

 

[penrow]

Super nice build, congrats! I think the cart system works great. It allows for a lot of on board power that dwarfs what could be had from the pre-built store bought units. Love the idea of the solar panel so the whole thing is a single self contained unit. Nice color scheme.

Thanks Electrobob, your wagon post was the inspiration! I love my wagon, it's solid and being able to reposition it so easily to track the sun really allows you to harvest a lot more power than a stationary panel. I will have the victron app open showing the watts coming in and I can rotate it left or right and dial it in to the exact position to get the most power. I haven't changed the angle of the panel since I mounted it to the wagon, seems like its doing great where its at, I hit 193 watts from a 200 watt rated panel, so I'm satisfied.