---
type: permanent
status: verified
source: "manohargupta.com/journal/esp32-dht11-iot (2026-01-25)"
tags: [knowledge, iot, hardware]
---
# 🌡️ IoT: ESP32 + DHT11 Monitoring
> First full-stack IoT build — a home-office temperature/humidity monitor (~$10).

## Hardware
- **ESP32** — microcontroller with WiFi + Bluetooth
- **DHT11** — affordable temp/humidity sensor
- Breadboard + jumper wires

## Architecture
`ESP32 (Arduino sketch, reads every 10s)` → **MQTT** → **Node.js backend** (store) → **React frontend** (subscribes to MQTT topic, real-time display).

## Lessons (his words)
- Microcontrollers are more accessible than expected
- **MQTT is elegant** for IoT comms
- Satisfying to see physical sensors drive web software

## Next
Off-grid: a solar panel to power a fully sun-powered sensor setup → ties to [[Renewables Overview|solar]] interest.

## Related
[[Engineering Overview]] · [[MOC - Software]] · [[Renewables Overview]]