Solar Tracking Systems

[AsTra Trackers]

Hello everyone,

my name is Pietro, and I am an electronics technician here, in Italy For some time now, I have been developing a controller for solar trackers that allows precise and reliable sun tracking.

I joined this forum to share experiences, learn from others, and connect with people who, like me, are passionate about solar energy and applied electronics.

If you’re interested, I’ve put some details about the project on my website: https://www.astratrackers.com

I hope to contribute with my project while also learning from your experiences.

Thank you for welcoming me to the community!

[sdold]

Are you using a microcontroller? Which one?

[AsTra Trackers]

Hi sdold, good morning from Italy and thank you for your question.

Yes, the controller is managed by micro RP2040, low cost (around 1 euro) but very good for this application.

The program running inside is not just about solar calculation...I truly believe I have considered all the possible situations that may arise during the design of a solar tracker.
Have you taken a look at the website?

You can download the "Getting Started Guide" from the website, a useful resource for tackling the challenge of building a professional solar tracker. The controller manual (a complete document with all explanations about how the controller works and how it should be used) is provided together with the board.

In the meantime, I am preparing the second version of a solar tracker shield for Arduino. In a few days, I will publish the SMD version. It is a low cost, single axis project, but fully featured, including the configurator (just like the controller I just told you about).

Unlike the dual axis controller (which can manage both AC motors and stepper motors), the Arduino Solar Tracker Shield can only handle stepper motors.


Pietro

[sdold]

It looks like a fun project. So if someone wanted to build something like this on their own, what would be a good approach to take? Is there a way to determine the panel angle based on your location and time of day? I assume this is for a single axis.

[AsTra Trackers]

The "professional" controller can manage one or two axes independently and offers many useful features.

The Arduino shield can only manage the azimuth axis, but it also offers many important features.

Both systems use our own solar algorithm that—based on geographic coordinates—returns the sun's angular degrees, azimuth, and elevation.

The technical manual explains in detail how to build a tracker and how to size the mechanical components of the structure (gearboxes, motors, etc.).

[sdold]

Are you willing to share any code or help others here that might want to build something like the board you have?

[AsTra Trackers]

Hi sdold,
i understood your question, but I prefer not to share the source code, as it represents years of development and testing.
However, if someone wants to build their own tracker from scratch, there are public resources that can be very helpful as a starting point:

• NOAA Solar Calculator (https://gml.noaa.gov/grad/solcalc/)
• NREL Solar Position and Intensity (SPA Algorithm) (https://midcdmz.nrel.gov/spa/)

These provide the astronomical algorithms to calculate the Sun’s position (azimuth and elevation) based on location and time.
That said, turning those formulas into a reliable and fully functional solar tracker — managing all the practical situations and exceptions — is the real challenge !!! and it’s exactly why I decided to design both my Solar Tracker Controller and the Arduino Solar Tracker Shield.

Have you taken a look at the PDF documents available on the two links I posted?
There isn’t any code, but there are excellent ideas for building a professional tracker, single and dual axis.

Pietro

[sdold]

Thanks for the link to the algorithms, there is a lot going on. It made more sense once I found the header file.
I think most of us here prefer the simplicity of a fixed system (with a few more panels to make up the difference) over a tracking system with additional costs and maintenance, but I'm sure there are those who would be interested in your ideas and maybe your product. Normally we don't allow advertising, but if you'd like to stay and talk system design and help others who might want to build a tracking system, I think leaving your link up would be OK as long as you don't use use this forum to promote your product. Is that a deal?

[AsTra Trackers]

Thanks for the reply, and sorry for the delay, due to my job as bus driver...

I agree with your thoughts (about a few more panels, rather than using a tracker) but - as you know - there are situations where available space is limited and a tracker can be really useful...

Thank you again for the opportunity you gave to me.

I'm available for further explanationa or assistance to anyone who wants to build their own tracker!!!

Pietro