Solar Powered WiFi Weather Station





Introduction: Solar Powered WiFi Weather Station

Microcontroller Contest 2017

First Prize in the
Microcontroller Contest 2017

In this Instructable, I am going to show you how to build a Solar powered WiFi Weather Station with a Wemos board.The Wemos D1 Mini Pro have small form-factor and wide range of plug-and-play shields make it an ideal solution for quickly getting started with programming the ESP8266 SoC. It is an inexpensive way to build Internet Of things ( IoT ) and is Arduino compatible.

The new Weather Station have following features:

1. The Weather Station can measure :Temperature, Humidity , Barometric Pressure , Altitude

2. You can monitor the above weather parameters from your Smartphone or from the web ( )

3. The whole circuit along with power supply is put inside a 3D printed enclosure.

4. The range of the device is enhanced by using an 3dBi external antenna .It is around 100 meter.

Step 1: Parts and Tools Required

1. Wemos D1 Mini Pro ( Banggood )

2. TP 4056 Charging Board ( Amazon / Aliexpress )

3. Diode ( Aliexpress )

4. BME 280 sensor ( Aliexpress )

5. Solar Panel ( Banggood )

6. Perforated Board ( Banggood )

7. Screw Terminals ( Banggood )

8. PCB standoffs ( Banggood )

9. Li Ion Battery ( Banggood )

10. AA Battery Holder ( Amazon )

11. 22 AWG wire ( Amazon / Banggood )

12. Super Glue ( Amazon )

13. Duct Tape ( Amazon )

14. 3D printing filament -PLA ( GearBest )

Tools Used :

1.3D Printer ( Anet A8/ Creality CR-10 Mini )

2. Soldering Iron ( Amazon )

3. Glue Gun ( Amazon )

4. Wire Cutter / Stripper ( Amazon )

Step 2: Power Supply

My plan is to deploy the Weather station at a remote place ( my farm house).To run the Weather Station continuously, there must be a continuous power supply otherwise the system will not work .The best way to provide continuous power to the circuit is by using a battery.But after some days the battery juice will run out, and it is really difficult job to go there and charge it. So a solar charging circuit was proposed to user free energy from the sun to charge the batteries and to power the Wemos board.I have used a 14450 Li Ion battery instead of a 18650 battery because of its smaller size.The size is same as of an AA battery.

The battery is charged from a Solar panel through a TP4056 charging module. The TP4056 module comes with battery protection chip or without the protection chip.I will recommend to buy a module which have battery protection chip included.

About the TP4056 Battery Charger

The TP4056 module is perfect for charging single cell 3.7V 1 Ah or higher LiPo cells. Based around the TP4056 charger IC and DW01 battery protection IC this module will offer 1000 mA charge current then cut off when charging is finished. Furthermore when the battery voltage drops below 2.4V the protection IC will cut off the load to protect the cell from under voltage.It also protects against over voltage and reverse polarity connection.

Step 3: Measuring the Weather Data

In the earlier days weather parameters like ambient temperature,humidity and barometric pressure were measured with separate analog instruments: thermometer, hygrometer and barometer.But today the market is flooded with cheap and efficient digital sensors that can be used to measure a variety of environmental parameters.The best examples are sensors like DHT11, DHT 22, BMP180, BMP280 etc.

In this project we will use a BMP 280 sensor.

BMP 280 :

BMP280 is a sophisticated sensor that very accurately measures barometric pressure and temperature with reasonable accuracy. The BME280 is the next-generation of sensors from Bosch, and is the upgrade to the BMP085/BMP180/BMP183 - with a low altitude noise of 0.25m and the same fast conversion time.

The advantage of this sensor is that it can use either I2C or SPI for communication with microcontroller. For simple easy wiring, I will suggest to by I2C version board.

Step 4: Using an External Antenna ( 3dBi )

The Wemos D1 mini Pro board have a inbuilt ceramic antenna along with provision for connecting an external antenna to improve the range.Before using the external antenna, you have to reroute the antenna signal from the built-in ceramic antenna, to the external socket.This can be done by rotating the small surface mount (0603) Zero Ohm resistor (sometimes called a link).

You can watch this video made by Alex Eamesto rotate the zero ohm resistor.

Then snap the antenna SMA connector in to the Wemos Pro mini antenna slot.

Step 5: Solder the Headers

Wemos modules come with variety of headers but you have to solder it according your requirement.

For this project,

1. Solder the two male headers to the Wemos D1 pro mini board.

2. Solder a 4 pin male header to the BMP 280 module.

After soldering the headers the module will look as shown in the above picture.

Step 6: Adding Headers and Terminals

Next step is soldering the headers to the perforated board.

1. First place the Wemos board over the perforated board and mark the foot print.Then solder the two row of female headers over the marked position.

2. Then solder a 4 pin female headers as shown in the picture.

3. Solder a screw terminals for battery connection.

Step 7: Mount the Charging Board :

Stick a small piece of double sided tap on the back side of the charging module and then paste it on the perforated board as shown in the picture.During mounting care should be taken to align the board in such a way that the soldering holes will match with the perforated board holes.

Adding terminal for Solar Panel

Solder a screw terminal just near the micro USB port of the charging board.

You can solder this terminal in the earlier step also.

Step 8: Wiring Diagram

First I cut small pieces of different colors wires and strip out the insulation at the both ends.

Then I solder the wires according to the Schematic diagram as shown in the above picture.

Wemos -> BME 280

3.3 V - -> Vin


D1 --> SCL

D2 --> SDA

TP4056 Connection

Solar Panel terminal -> + and - near the micro USB port

Battery Terminal -> B+ and B-

5V and GND of Wemos -> Out+ and Out-

Note :In the beginning , I forgot to solder the diode.Later I solder it near to the Solar panel terminal and connect it as per the wiring diagram.I have used a 1N4007 diode but I will recommend to use a low voltage drop schottky diode.

Step 9: Designing the Enclosure

This was the most time consuming step for me.I have spent around 4 hours to design the enclosure. I used Autodesk Fusion 360 to design it. The enclosure have two parts : Main Body and Front Cover

The main body is basically designed to fit all the components. It can accommodate the following components

1. 50x70mm circuit board

2. AA battery holder

3. 85.5 x 58.5 x 3 mm Solar Panel

4. 3dBi external antenna

Download the .stl files from Thingiverse

Step 10: 3D Printing

After completion of design, it is time to 3D print the enclosure.In Fusion 360 you can click on make and slice the model by using a slicer software.I have used cura to slice the model.

I used an Anet A8 3D printer and 1.75 mm green PLA to print out all the body parts. It took me about 11 hours to print the main body and around 4 hours to print the front cover.

I will highly recommend to use another printer for you that is Creality CR - 10. Now a mini version of the CR-10 is also available.The Creality printers are one of my favorite 3D Printer.

As I am new to 3D designing, my design was not optimistic.But I am sure, this enclosure can made by using lesser material ( less print time ). I will try to improve the design later.

My settings are:

Print Speed : 40 mm/s

Layer Height : 0.2

Fill Density : 15%

Extruder Temperature : 195 degC

Bed Temp : 55 degCr

Step 11: Installing the Solar Panel and Battery

Solder a 22 AWG red wire to the positive terminal and black wire to the negative terminal of the Solar panel.

Insert the two wires in to the holes in the roof of the main enclosure body.

Use super glue to fix the Solar Panel and press it some time for proper bonding.

Seal the holes from the inside by using hot glue.

Then insert the battery holder in to the slot at the bottom of the enclosure.

Step 12: Installing the Antenna

Unscrew the nuts and washers in the SMA connector.

Insert the SMA connector in to the holes provided in the enclosure.See the image above.

Then tighten the nut along with the washers.

Now install the antenna by properly aligning with the SMA connector.

Step 13: Installing the Circuit Board

Mount the standoffs at 4 corners of the circuit board.

Apply super glue at the 4 slots in the enclosure. Refer the above picture.

Then align the standoff with the 4 slots and place it.leave some to dry it out.

Step 14: Close the Front Cover

After printing the front cover, it may be not perfectly fit to the main enclosure body.If it is the case, just sand it at the sides by using a sand paper.

Slide the front cover in to the slots in the main body.

To secure it, use duct tape at the bottom.

Step 15: Programming

To use Wemos D1 with the Arduino library, you'll have to use the Arduino IDE with ESP8266 board support. If you haven't already done that yet, you can easily install ESP8266 Board support to your Arduino IDE by following this tutorial by Sparkfun.

Following settings are preferable :

PU Frequency:
80MHz 160MHz

Flash Size: 4M (3M SPIFFS) – 3M File system size 4M (1M SPIFFS) – 1M File system size

Upload Speed: 921600 bps

Arduino Code for Blynk App :

Sleep Mode :

The ESP8266 is a pretty power hungry device. If you want your project to run off a battery for more than a few hours, you have two options:

1. Get a huge battery

2.Cleverly put the Thing to sleep.

The best choice is the second option.Before using the deepsleep feature, Wemos D0 pin must be connected to the Reset pin.

Credit : This was suggested by one of the Instructables user " tim Rowledge ".

More Power Saving Option :

The Wemos D1 Mini has a small LED that lights when the board is powered.It consume lot of power.So just pull that LED off the board with a pair of pliers. It will drastically drop the sleep current down .

Now the device can run for long time with a single Li Ion battery.

#define BLYNK_PRINT Serial    // Comment this out to disable prints and save space<br>#include < ESP8266WiFi.h>
#include  <BlynkSimpleEsp8266.h ></p><p>
#include "Seeed_BME280.h"
#include < Wire.h>
BME280 bme280;
// You should get Auth Token in the Blynk App.
// Go to the Project Settings (nut icon).
char auth[] = "3df5f636c7dc464a457a32e382c4796xx";// Your WiFi credentials.
// Set password to "" for open networks.
char ssid[] = "SSID";
char pass[] = "PASS WORD";
void setup()
  Blynk.begin(auth, ssid, pass);
  Serial.println("Device error!");

void loop()
  //get and print temperatures
  float temp = bme280.getTemperature();
  Serial.print("Temp: ");
  Serial.println("C");//The unit for  Celsius because original arduino don't support speical symbols
  Blynk.virtualWrite(0, temp); // virtual pin 0
  Blynk.virtualWrite(4, temp); // virtual pin 4
  //get and print atmospheric pressure data
  float pressure = bme280.getPressure(); // pressure in Pa
  float p = pressure/100.0 ; // pressure in hPa
  Serial.print("Pressure: ");
  Blynk.virtualWrite(1, p); // virtual pin 1
  //get and print altitude data
  float altitude = bme280.calcAltitude(pressure);
  Serial.print("Altitude: ");
  Blynk.virtualWrite(2, altitude); // virtual pin 2  //get and print humidity data
  float humidity = bme280.getHumidity();
  Serial.print("Humidity: ");
  Blynk.virtualWrite(3, humidity); // virtual pin 3
  ESP.deepSleep(5 * 60 * 1000000); // deepSleep time is defined in microseconds.

Step 16: Install Blynk App and Library

Blynk is an app that allows full control over Arduino, Rasberry, Intel Edision and many more hardware.It is compatible for both Android and IPhone.Right now the Blynk app is available with free of cost.

You can download the app from the following link

1. For Android

2. For Iphone

After downloading the app, installed it on your smartphone.

Then you have to import the library on to your Arduino IDE.

Download the Library

When you run the app for the first time, you need to sign in – so enter an email address and password. Click the “+” at the top-right of the display to create a new project.Then name it.

Select the target hardware " ESP8266 "Then click “E-mail” to send that auth token to yourself – you will need it in the code

Step 17: Make the Dash Board

The Dashboard is consists of different widgets.To add widgets follow the steps below :

Click “Create” to enter the main Dashboard screen.

Next, press “+” again to get the “Widget Box”

Then drag 4 Gauges.

Click on the graphs,it will pop up a settings menu as shown above.

You have to change the name "Temperature",Select the Virtual Pin V1, then change the range from 0 -50.Similarly do for other parameters.

Finally drag a graph and repeat the same procedure as in gauge settings.The final dashboard picture is shown in the above picture.

You can change the color also by clicking the circle icon on the right side of the Name.

Step 18: Uploading Sensor Data to ThingSpeak

First create an account on ThingSpeak.

Then create a new Channel on your ThingSpeak account.
Find How to Create a New Channel

Fill Field 1 as Temperature ,Field 2 as Humidity and Field 3 as pressure.

In your ThingSpeak account select “Channel” and then “My Channel”.

Click on your channel name.

Click on “API Keys” tab and copy the “Write API Key”

Open the Solar_Weather_Station_ThingSpeak code .Then write your SSID and Password.

Replace the “WRITE API ”with the copied “Write API Key”.

Required Library : BME280

Credit : This code is not written by me .I got it from the link given in a YouTube video by plukas.

Step 19: Final Test

Place the device on sunlight, the red led on TP 4056 charger module will lit up.

1. Blynk App Monitoring:

Open the blynk project.If everything is Ok,you will notice the gauge will live and the graph stat to plot the temperature data.

2. ThingSpeak Monitoring :

First open your Thingspeak Chanel.

Then go to “Private View” tab or “Public View” tab to see the Data Charts.

Thanks for reading my Instructable.

If you like my project, don't forget to share it.

7 People Made This Project!


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3 Questions

what type of metals you used?

i want steps of operate wifi by solar power
thank you

It's possible to use old version of TP4056 Charging board (whitout OUT +/-). It's necessary a sort of booster for powering Wemos board?

Hi mrkrash, the main function of the TP4056 is to protect the battery from being overcharged. The versions with OUT+- also have over-discharge protection. although this is very desirable, it is not essential to make the project work. You can connect the WeMos D1 min pro directly to the Bat +- terminals.


Hello, I built this project and it's measuring data perfectly but i have problems with charging the battery. At first everything was working properly, data was sent to Blynk and I could see it on my phone. But then battery got under some voltage and weather station died. I measured voltage with multimeter and it looks like output of solar panel is somewhere between 4 and 5.5 V depending on level of brightnes. Red LED on TP4056 is on and I thought that battery is charging but after half day on my balcony, voltage of battery didn't get higher than 3V. When I measured OUT pins of TP4056 there were no curent. Can you please sugest somthing that could be problem?

Hello PitrP, I had similar problems myself. Are you using sleep mode for the WeMos board? If not, I think that the solar panel may not be able to keep up with the power consumption of the WeMos.

For a start, I think you should try plugging in a USB cable with mains power into the TP4056 and leave it for at least a few hours (maybe a day). That should get your battery fully charged. It would be worth while to measure the battery voltage as well as the output voltage of the solar panel.

I have been running my implementation with a 10 minute sleep cycle for several months now with no battery problems. I found that with a 1 minute sleep cycle the panel could not keep up with the power usage. I have not tried periods in between 1 and 10 minutes.

I am also using the WeMos to measure its own Vcc (effectvely the battery voltage) and reporting that to Blynk, so that I can see how the voltage varies through the day. Typically the daily cycle goes from 3.8V early in the morning to 4.1V when the full sun is on the panel.

Good afternoon . How are you? Forgive my limited knowledge of English. I have soldered the components on the PCB board, I have installed the codes of the following programs:

Solar_Powered_Weather_Station.ino -> Here I put the Token of the Blynk application.

Solar_Weather_Station_ThingSpeak.ino -> Here I put the api_key that I get from the page

I have entered the two schedules and I have not had any problems ... But I can not get the weather station to detect me in the Blynk program. And the thingspeak page does not register the data. That is, I have put the programming to the station but I can not read the data anywhere.

Could you help me please?

Thank you very much

Hi brosvv1, Maybe I can help you best with the Blynk version.

I think you should try removing the comment-out slashes in line 28, so as to enable serial printing from the Blynk library. So this line will now read

#define BLYNK_PRINT Serial // Comment this out to disable prints and save space

If you can't work out what is the problem, please post the output from the serial monitor here so that I can look at it, and may be able to give further advice.

Good afternoon, how are you?I tried to make the weather station work but I have not succeeded, I have deleted the line that you mention to me but it does not do anything to me, I have looked through the serial monitor and it does not show me any information. The station shows the red light blinking, but I can not gather any information. Could you help me? Thank you very much

Best regards

Hi borsvv1, I am sorry about the delay I must have missed your reply.

Do you mean, the serial monitor is blank (no content at all) or do you mean there is nothing useful there? If it is showing nothing at all, it is probably because its settings are different from the software. If it is showing something, anything at all, please post it in your reply.

Hi all, I have build it and have a working prototype with the Blynk and Thingspeak. My question is what kind of distance can I expect for the wireless connection with the external antenna.

Regards Geoff

I have been getting about 50 metres with the external antenna and about 20 metres with the built-in antena. It depends a lot on the local conditions, including the base station that you are using and obstacles in between the base and your project hardware.

Hello, i know this error was here countless time but i tried all the tips below and didnt work.. so if you have some new tip i would be gratefull..

warning: espcomm_sync failed
error: espcomm_open failed
error: espcomm_upload_mem failed
error: espcomm_upload_mem failed

Hi Rengatharu, Can you post a more complete version of the output, going from the time compilation is finished to the end?

Have you tried uploading your sketch multiple times and it fails every time?

What are the settings you are using in the Tools menu?

I hope we can help you. Keith