ESP32 Project Ideas and What the Board Is Actually Good At
Ten ESP32 projects that use what the board offers, plus the pin and ADC quirks that catch students out.
What the ESP32 is genuinely good at
- Wi-Fi and Bluetooth on the board, with no extra module or level shifting.
- Enough memory to buffer readings through a network outage.
- Deep sleep in the microamp range, which makes battery projects practical.
- Two cores, so networking does not stall your sensor timing.
- Plenty of ADC channels and hardware PWM for motor and lighting control.
Ten projects that use those strengths
Weather station with buffered upload
Uses the memory and the Wi-Fi properly, not just as a sensor readout.
See this projectHome automation with dual control
Wi-Fi and physical switches kept in sync, with state saved to flash.
See this projectEnergy monitoring with fast sampling
Sampling voltage and current together many times per cycle needs the extra speed.
See this projectBattery-powered soil sensor node
Deep sleep between readings so a node runs for weeks on a cell.
See this projectNon-contact tank level monitor
Ultrasonic measurement with alerts and daily consumption logging.
See this projectBluetooth sensor bridge to a phone app
Uses BLE rather than Wi-Fi — useful where there is no network at all.
Web-server device configuration portal
The ESP32 hosts its own setup page for Wi-Fi credentials and thresholds.
Multi-zone temperature logger
Several sensors on one bus, logged and charted over days.
Smart door lock with logging
Keypad or RFID entry with a timestamped access record.
See this projectAir quality node with an index and alerts
Gas and particulate sensing reduced to one number people can act on.
Quirks that cost students an evening
ADC2 pins do not work while Wi-Fi is active. If an analogue reading goes dead the moment you connect to a network, this is why — move the sensor to an ADC1 pin.
Several GPIOs are strapping pins that must be at particular levels at boot. Attaching a sensor that pulls one of them low will stop the board booting, which looks like a dead board and is not.
The ADC is not linear near the top and bottom of its range. For measurement projects, calibrate across the range you actually use, and say in your report that you did.
Not every pin can be an output. Some are input-only, which is easy to miss when you are planning your wiring on paper.
Powering it properly
The ESP32 draws current spikes when the radio transmits, and a weak supply causes brownout resets that appear random. Use a supply with adequate headroom and a decoupling capacitor near the board — it resolves a surprising proportion of "unstable ESP32" problems.
