Language:
English (current) | Русский (Russian)

☀️ ESP8266 Weather Station (HTU21D + TSL2561) with Solar Power and ThingSpeak

This project is an autonomous outdoor weather station built around the ESP8266 (ESP-12E) microcontroller. It measures temperature, humidity, illuminance (lux), dew point, and heat index, then sends the data to ThingSpeak every 15 minutes.

⚡️ Key Highlights

• Solar-powered (using TP4057 and a LiPo 2000 mAh battery)
• Deep Sleep for energy efficiency (15 minutes)
• Sensors:
  • HTU21D for temperature and humidity
  • TSL2561 for illuminance
• Calculates dew point and heat index
• Uses AMS1117 (3.3 V) as a linear regulator (simple but not very power-efficient)

ThingSpeak Channel

• 👉 Live data: ThingSpeak link

3D-Printed Enclosure

• 👉 We use a 3D-printed case to protect the device:
  Thingiverse Model

---

🧷 Features

1. ESP8266 (ESP-12E) – Wi-Fi connectivity and data transmission
2. HTU21D – temperature & humidity measurements
3. TSL2561 – illuminance measurement (lux)
4. Dew Point & Heat Index – computed from sensor data
5. Data Upload to ThingSpeak – via simple HTTP GET requests
6. Solar Power – recharges a LiPo battery through TP4057
7. Deep Sleep (15 min) – minimizes power consumption
8. AMS1117 – used between the LiPo and the ESP8266 (simple, but draws ~5–10 mA quiescent current)

---

🛠 Hardware Components

Component	Purpose
ESP-12E (ESP8266)	Main microcontroller with Wi-Fi
HTU21D	Temperature & humidity sensor
TSL2561	Illuminance (lux) sensor
TP4057	LiPo charging module
LiPo 2000 mAh	Rechargeable battery
AMS1117 (3.3 V)	Linear regulator (simple but not the most efficient)
5V Solar Panel	Charges the battery via TP4057
3D-printed enclosure	Protects the device from weather (Thingiverse design)

Note on AMS1117: It is easy to use but has a relatively high quiescent current (5–10 mA), which reduces battery life. For better efficiency, consider a low-dropout regulator (e.g., MCP1700) or a DC-DC converter.

---

🔌Wiring

1. Sensors (I²C)

HTU21D → ESP8266

VCC -> 3.3V
GND -> GND
SDA -> GPIO4 (D2)
SCL -> GPIO5 (D1)

TSL2561 → ESP8266

VCC -> 3.3V
GND -> GND
SDA -> GPIO4 (D2) [shared with HTU21D]
SCL -> GPIO5 (D1) [shared with HTU21D]

🔋 2. Power (Solar + TP4057 + LiPo + AMS1117)

• Solar Panel (5V) → TP4057 IN
• TP4057 OUT → LiPo battery (3.7 V nominal)
• LiPo → AMS1117 VIN
• AMS1117 VOUT → 3.3 V to power the ESP8266

3. ESP8266 Pins

Pin	Connection
VCC	3.3V (from AMS1117)
GND	GND
EN	3.3V via 10kΩ resistor (CH_PD)
GPIO16	Connect to RST (for Deep Sleep)
GPIO0	GND during flashing, then 3.3V (via 10kΩ)
GPIO2,15	Standard ESP8266 boot configuration

---

🖥 Arduino IDE Setup

1. Install Arduino IDE from the official website.
2. In Arduino IDE, go to:

   File > Preferences > Additional Boards Manager URLs
   

   and add:

   https://arduino.esp8266.com/stable/package_esp8266com_index.json
   

3. Open Boards Manager (Tools > Board > Boards Manager), search for esp8266, and install "ESP8266 by ESP8266 Community".
4. Choose Generic ESP8266 Module (or NodeMCU 1.0) in the Tools > Board menu.

---

📚 Required Libraries

• ESP8266WiFi (bundled with ESP8266 platform)
• Wire (standard I²C library)
• Adafruit HTU21DF
• Adafruit Unified Sensor
• Adafruit TSL2561
• ESP8266HTTPClient (bundled with ESP8266 platform)

Install them via Sketch > Include Library > Manage Libraries in Arduino IDE.

---

💡 Flashing the ESP8266

1. Connect ESP8266 to your PC via a USB-UART adapter (e.g., CH340, FTDI).
2. Enter flashing mode:
   • GPIO0 → GND
   • RESET (toggle) or power-cycle
   • Now the ESP8266 is ready for programming
3. Select the correct board (e.g., Generic ESP8266) and serial port in Arduino IDE.
4. Upload the sketch.
5. After successful flashing, disconnect GPIO0 from GND (pull it up to 3.3V), then reset the module.

---

🕐 Adjusting the Data Send Interval

The code uses Deep Sleep for power saving. The default sleep time is 15 minutes, set in microseconds:

#define SLEEP_TIME 900e6  // 15 minutes (900,000,000 µs)

• 1 second = 1e6 µs
• 1 minute = 60 * 1e6 µs
• Example: 5 minutes = 300e6, 30 minutes = 1800e6

Important: Connect GPIO16 to RST so the ESP8266 can wake from Deep Sleep.

---

ThingSpeak Fields

Field	Description	Unit
Field1	Temperature	°C
Field2	Humidity	%
Field3	Illuminance	lux
Field4	Dew Point	°C
Field5	Heat Index	°C

Set your Wi-Fi credentials and ThingSpeak API key in the sketch:

// Wi-Fi settings
#define STASSID "your_wifi_ssid"
#define STAPSK  "your_wifi_password"

// ThingSpeak API
const char* apiKey = "your_thingspeak_api_key";
const char* server = "api.thingspeak.com";

---

Power Consumption Notes

• Using AMS1117 is straightforward, but it has a relatively high quiescent current (5–10 mA).
• This can limit battery life in long-term operation.
• For better efficiency, use a low-quiescent-current LDO (e.g., MCP1700, HT7333) or a DC-DC converter.

---

🏁 Future Plans

• Add a UV sensor (e.g., VEML6075)
• Integrate MQTT for Home Assistant or Node-RED
• Create a local web interface for real-time data visualization

---

📜 License

This project is released under the MIT License. Feel free to use, modify, and distribute!

If you have any questions or suggestions, open an Issue.