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3KUdelta / Solar_WiFi_Weather_Station

Based on the work of Open Green Energy: First solar Zambretti Forecaster
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Suggestion: modifying the TP4056 to operate closer to the MPP of the panel #52

Open FBMinis opened 11 months ago

FBMinis commented 11 months ago

It is explained here that these little 5V panels will never deliver the 1A current the TP4056 is setup to pull:

https://youtu.be/37kGva3NW8w?t=320

I have determined that the MPP of my solar panel under full sunlight is reached with current around 80mA using this test method:

https://makersportal.com/blog/solar-panel-characterization-and-experiments-with-arduino https://wolles-elektronikkiste.de/en/ina219-current-and-power-sensor

I suggest replacing the 1.2K resistor on the TP4056 with a 20K trimmer potentiometer and slowly increase the resistance until the power value reaches a maximum.

Simple_method_for_I-V_characterization_curve_for_l.pdf

Sunlight based I-V characterization of solar PV.pdf

Thank you for your project, I'm going to try to build it. The code is very well commented, I think it will be straightforward.

Regards

3KUdelta commented 11 months ago

Thank you for your valuable input. My stations have been running flawlessly for several years now and the battery keeps charging perfectly. I am curious about your result. Marc

FBMinis commented 11 months ago

That is motivating to know, thank you!

Regarding the BME280, have you had any trouble reading humidity values? I have had one outside for 3 months now and it started reading 100% most of the day. I searched online and many people complain about this.

3KUdelta commented 11 months ago

Yes, it needs to be recalibrated once a while. In these cases I take the station to the inside for 24 hours and this will do the trick. However, I struggled much more with the BME's temperature readings that's why I added an extra temp sensor.

FBMinis commented 11 months ago

Regarding the BME280 stuck to 100% RH, I left it inside a small container covered with isopropanol for a few hours, dried it with a paper towel and then with a blow dryer (as hot as I could). The readings are now in line with other sensors I had around, we'll see for how long.

I'm running your code on an ESP32-CAM that I have outside facing the horizon. Regarding SPIFFS frequent read/write, have you noticed any degradation of your units?

3KUdelta commented 10 months ago

Thank you for your feedback - very interesting build. Maybe you want to share one day your code in your fork of this project. After all these years outside I never was facing any problems nor with SPIFFS (besides of the case printed in PLA which kind of melted this year). Marc