MicroEnv v1.x
MicroEnv is a compact and simplistic environmental monitoring sensor, based on the ESP32-C3 and the Sensirion SGP30 and SHT45 sensors, using ESPHome for integration with HomeAssistant
Use a MicroEnv near a source of emissions to monitor air quality, or as a general room environmental tracking sensor.
Power is provided by USB-C, though a very slim cable is required when using SMD soldering without a buffer.
The Sensirion sensors are elevated with through-hole pins, to ensure optimal distance between the (warm) board and the sensors themselves.
For more details, please see my blog post on the MicroEnv project.
Parts List
| Qty | Component | Cost (2025/05 CAD, ex. shipping) | Links |
|---|---|---|---|
| 1 | GY-SGP30 | $5.73 | AliExpress |
| 1 | GY-SHT45 | $5.67 | AliExpress* |
| 1 | ESP32-C3 | $3.12 | AliExpress |
| 1 | Custom PCB (JLC) | $0.50 ($5.00/10) | GitHub |
| TOTAL | $15.02 |
* Ensure you select the correct device on the page as it shows multiple options.
Configurable Options
There are several UI-configurable options with the MicroEnv to help you get the most out of the sensor for your particular use-case.
Temperature Offset (selector, -30 to +10 @ 0.1, -5 default)
Allows calibration of the SHT45 temperature sensor with an offset from -30 to +10 degrees C. Useful if the sensor is misreporting actual ambient tempreatures. Due to internal heating of the SHT45 by the ESP32, this defaults to -5; further calibration may be needed for your sensors and environment.
Humidity Offset (selector, -20 to +20 @ 0.1)
Allows calibration of the SHT45 humidity sensor with an offset from -20 to +20 percent relative humidity. Useful if the sensor is misreporting actual humidity.