Arduino solar/sun tracker with data logger

This project by a final year student from university of liverpool is about monitoring the solar energy emitted by sun using solar panels and arduino. Data acquisition and logging is also part of the project. A single arduino mega, 20×4 lcd, arduino SD card module and 2 small solar panels are part of the project.

Solar sun tracker project over view

Two solar panels are used to grab the solar energy. Both the solar panels are of same size and are of same rating. One solar panel is fixed and the other one is movable residing on a motor. The idea behind one stable and the other movable is to figure out which topology works effectively and grabs more energy. Data logger is used to log data from both the solar panels. This data after few hours is extracted form arduino SD card and plotted on two different graphs for comparison.

Arduino uno single solar tracker circuit

The two solar cells are connected to a single arduino mega in the final circuit. But first the individual solar cell is tested to verify that the system/circuit which is under consideration will work efficiently. The individual solar cell circuit is shown in below figure.

Arduino solar tracker circuit diagram

In the above figure arduino uno is interfaced with lcd. On lcd the voltage and current output of the solar panel is displayed. Total power output by solar panel is also displayed on the lcd. Lcd is interfaced with arduino in 4-bit mode. Solar panel is not directly connected to arduino. Instead a 4066 multiplexer switch is used in between arduino and solar panel. 4066 prevents the arduino analog pins from continuous potential. 4066 pins are controlled by arduino digital pins. So when we want to monitor the power output by solar panel we short circuit the connection. We can also use relay here but relay consumes more power. Hence 4066 is best fit in this circuit.

How the power is monitored?

I know every one is thinking about how the arduino is monitoring power? Well i wrote a nice tutorial on techniques how to monitor power(Dc voltage). I encourage you to go through these tutorials because answer lies in these tutorials.

Final hard ware circuit built is below. Output voltage, current and power is displayed on the lcd screen. Note in the hard ware circuit below SD card is also used to log data on sd card.

Arduino solar energy monitoring system

Solar tracker result

Instantaneous solar energy data is displayed on lcd screen where as full log is displayed on arduino serial monitor.

arduino solar tracker result on arduino serial monitor

Working with both solar panels

After individual solar panel testing its time to design the final project. Both the panels are connected to arduino mega. Arduino sd card and 4066 ics are mounted on vero board. The final project hardware is shown below. Panel 2 is mounted on a movable structure.

Arduino mega with dual solar panels

4066 multiplex switch ic and arduino sd card module is mounted on vero board. Vero board circuit connections are shown in below figure. They are pretty messy 🙂

Arduino mega dual solar panel monitoring

Arduino solar monitoring results

After deploying the project/hardware in field data is logged in arduino sd card. Then after some time data is extracted from the sd card module and plotted on graphs in Microsoft excel. Results show that the movable panel slightly absorbs more energy compared to the fixed one.

Arduino solar monitoring graph plotting

Future work

Well in my opinion the project can be taken further and many outstanding features can be added to it.

Putting the arduino on web and sending the real time data to a remote server where web application shows the real time logged data on dials. I made a similar project like it on which i displayed the data on a remote website Esp8266 Thing Speak data logging
Movable solar panel works on electrical motor which is extra power consumption compared to the fixed one. Movable panel power consumption should also be considered and result should be recalculated.