diy solar

diy solar

Making a Dual Axis Tracker

Tracking VS fixed.

Today my;

2 panel dual axis tracker made 4.1 kWh of energy.

20 panel roof mounted made 32 kWh

2.05 per panel dual axis solar tracker.
0.65 per panel roof mounted fixed angle.

This is not the 30 to 35% more production, this 315%.

The dual axis panels are larger 72 cell panels the roof mounted are 60 cell panels. That would account for about 17% by it self. The roof are 310 watt and the dual axis are 340 watt rated panels,that could be another 9%.

~35% just due to size and rating. All the rest due to being perpendicular to the sun.

The cost of the dual axis setup I made is roughly $700. I did it all using spare parts except for the controller and actuators.
 
Oops.

whoops I divided some backwards.

32 / 20 = 1.6 kWh per panel

4.2 / 2 = 2.05 kWh per panel.

2.05 / 1.6 = 1.28 ; 28% lol so factor in size and rating, they did 7% worse than fixed. ??
 
Neat project! And well documented…love the Timelapse’s.

At the start of this thread, it was discussed that EcoWorthy Solar Tracker on Amazon was pretty expensive, but I think the price has come way down. And, I can’t easily do what you have done. But I absolutely appreciate your priority with a tracking system.

So, is the Ecoworthy a good investment? Especially currently at under $500? It just doesn’t get great reviews. But then nothing on Amazon does. There is always somebody that has a rotten experience with everything sold…like fake review from competitors…or poor quality control…or both.

But for sure, I am limited on the number of panels…6 total on two inputs of the Bluetti AC300. So, I can’t just stick panels every direction. I do have a pasture with lots of open sunny space. And was thinking at the very least two pole ground mounts with the ability to manually rotate on days when I am home and use more power (we don’t run AC when not at home), etc. And, just in the last few weeks of bringing my system on line, with only 3 panels connected, I have manually tracked the sun as I learned about my system.

I have SEG 460w…45”x73”. So part of the answer is if the EcoW system could handle 3 panels (49lbs each). The recommended panel setup from EcoW is 120lbs of 6 x 195w panels…less than 3 of my panels at 150lbs. Probably too much??

Thanks for any feedback!
 
But for sure, I am limited on the number of panels…6 total on two inputs of the Bluetti AC300. So, I can’t just stick panels every direction.

Why not?
Two strings of panels, different orientation and connected in parallel, will not both produce full current at the same time. But as a set they will produce good current for more hours.

Consider 2s2p into each input, 8 panels total. With orientations such that area presented to sun never exceeds area of 6 panels.
 
Two strings of panels, different orientation and connected in parallel, will not both produce full current at the same time. But as a set they will produce good current for more hours.
Consider 2s2p into each input, 8 panels total. With orientations such that area presented to sun never exceeds area of 6 panels.
Hmmm...well, I guess because I don't know better, and hadn't planned for that.

I bought 7 x 460w panels with the idea that 6 would go to the two PV inputs allowing for 1200w max per input, 123v, 13a on each of PV1 and PV2.

Each 3s would be be on its own pole. Even with out the Automated tracker, I was going to use @MichaelK 's setup with a pole over pole and be able to articulate the poles manually as needed...or slightly different from each other to cover South and South West bias.

The 7th panel was bought for two reasons...one to have an identical back up. But also for a direct feed into the battery, in a different location also...roof mount on a shed...near the inverter.

So, at this point, I only have 6 panels available for use.

If I did get two more panels (would require another weekend day trip to Houston), what would I gain with 2s2p vs 2 x 3s? (is that expressed correctly?)

Thanks for your time!
 
A single 2s2p is 4 panels. Two sets of 2s2p would be 8 panels.
8 panels due South optimal tilt for your latitude gives greatest production total for a year, but exceeds the wattage and current you want.
With something like SE and SW orientation and some tilt, you would get less total production but stay within limits and probably get more production than two sets of 3s for 6 panels.

I've usually considered a 90 degree angle between panels, 0.7x the area presented to sun compare to both oriented the same.
Another alternative, 60 degree acute angle would have 0.5x the area, in other words 3s2p could produce same power as 3s, but for even more hours. Such a configuration is tilted closer to vertical, so clipped sooner by sun at horizon.

I'm just starting to add off-angle strings. My original setup had all panels aimed at 2:00 PM sun for time of use rates.

You could play with an insolation tool to determine production for various months depending on tilt and orientation.

To the first order I would consider area presented to the sun by panels of multiple orientation. I'm sure there are second order effects, angle of light hitting glass, etc.

There is also different efficiency for PV voltage from 2s vs. 3s. Also make sure 2s doesn't drop below minimum MPPT voltage under hot conditions.

You could configure 4 panels as 2p2s to test this into one input and project what two sets would do.
 
Thanks for your reply which I read several times. I didn’t want to ask more questions until I did more research. I did end up going 3s for both PV1 and PV2 for the time being. But I left room for the 7th panel should I decide I need to do more or something different. So far, all 6 panels have been doing very well, charging the single 3kw battery by 11:00 am. I have another battery coming in…so it will be interesting to se how the system does.

Thanks again for the help!!
 

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