Iot Microcontroller Integration With Solar Energy Harvesting

Introduction

As the Internet of Things (IoT) continues to expand, energy management in IoT devices becomes increasingly important. One approach to solving this challenge is integrating renewable energy sources such as solar energy, to power these devices. This blog post will discuss an IoT solution using a popular microcontroller, ESP8266, and a solar energy harvesting system.

Solar Energy Harvesting Components

In order to incorporate solar energy in our IoT project, we need the following components:

1. Solar Panel: A source that converts sunlight into electricity. A small 5V solar panel can be used for this application.
2. Power Management IC: An IC that manages the harvested energy by regulating the input voltage and charging the battery, e.g., the CN3065 Lithium Battery Solar Controller Module.
3. Battery: A rechargeable LiPo battery to store the harvested solar energy.
4. ESP8266: A low-power microcontroller with built-in Wi-Fi.

Circuit Diagram

Connect the components as shown in the schematic below:

• Solar Panel: +5V to IN+ on CN3065 module, GND to IN- on CN3065 module
• CN3065 module: BAT+ to battery +, BAT- to battery -
• Battery: + to ESP8266 Vin, - to ESP8266 GND
• ESP8266: Connect to a sensor, actuator, or other components as required by your IoT project

Note: Use appropriate resistors, capacitors, and protection diodes as per your components' specifications.

ESP8266 Programming

For this example, we will use the integrated ESP8266 with a DHT11 temperature and humidity sensor. The ESP8266 will read the data from the sensor, connect to Wi-Fi, and send the data to an MQTT server.

First, install the required libraries in the Arduino IDE:

1. ESP8266WiFi.h - ESP8266 Wi-Fi library
2. PubSubClient.h - MQTT library
3. DHT.h - Library for using DHT11 sensor

Now, upload the following code to your ESP8266. Replace YOUR_SSID, YOUR_WIFI_PASSWORD, YOUR_MQTT_SERVER, and YOUR_MQTT_TOPIC with the appropriate information.

#include <ESP8266WiFi.h>
#include <PubSubClient.h>
#include <DHT.h>

// Wi-Fi and MQTT Configuration
const char* ssid = "YOUR_SSID";
const char* password = "YOUR_WIFI_PASSWORD";
const char* mqtt_server = "YOUR_MQTT_SERVER";
const char* mqtt_topic = "YOUR_MQTT_TOPIC";

// DHT11 Configuration
#define DHTPIN D5
#define DHTTYPE DHT11
DHT dht(DHTPIN, DHTTYPE);

// Initialize Wi-Fi and MQTT instances
WiFiClient espClient;
PubSubClient client(espClient);

// Function to reconnect to MQTT
void reconnect() {
  while (!client.connected()) {
    if (client.connect("ESP8266")) {
      break;
    }
  }
}

void setup() {
  Serial.begin(115200);
  dht.begin();
  WiFi.begin(ssid, password);
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
  }
  client.setServer(mqtt_server, 1883);
}

void loop() {
  if (!client.connected()) {
    reconnect();
  }

  float humidity = dht.readHumidity();
  float temperature = dht.readTemperature();

  String data = "Temperature: " + String(temperature) + " °C, Humidity: " + String(humidity) + " %";

  // Publish data to MQTT
  client.publish(mqtt_topic, data.c_str());

  delay(60000); // Send data every minute
}

With the code uploaded, your IoT device should now read the temperature and humidity and publish the data to your MQTT server, all powered by solar energy!

Conclusion

In this blog post, we have discussed a renewable energy solution for IoT devices using solar energy harvesting. We have gone through the components needed, the circuit diagram, and an example implementation using an ESP8266 microcontroller. Integrating solar energy with IoT devices is an effective method for enhancing their sustainability and efficiency.