Home Energy Monitor (v2)

⚠️ This is a work in progress. By no means is this production ready.

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ESP32-based Home Energy Monitor: monitors electricity consumption of your entire house with a single CT sensor.

Structure

This project consists out of multiple components:

Folder	Description	Build status
src-app	Mobile app (Ionic)	n/a
src-aws	Serverless AWS backend + GraphQL API
src-esp32	Firmware for the ESP32 (measuring device)

(TODO: add instructions on how to deploy all of this. 😅)

Video explanation

https://www.youtube.com/watch?v=ah3ezprtgmc

Read my blog post for more instructions: https://savjee.be/2019/07/Home-Energy-Monitor-ESP32-CT-Sensor-Emonlib/

Cloud Architecture

This is the cloud architecture that powers the energy meter and the app:

In a nutshell:

• The ESP32 has a MQTT connection with AWS IoT Core
• Every 30 seconds, 30 measurements are sent to AWS
• These measurements are stored in DynamoDB (IoT Rule)
• Once a day, all readings from the previous day are archived to S3
• A GraphQL API (hosted on Lambda) exposes the data stored in DynamoDB

Screenshots

Web dashboard, built on top of the GraphQL API:

What is displayed on the ESP32 OLED display:

DIY Requirements

To build your own Energy Monitor you need the following hardware:

• ESP32
• CT sensor: YHDC SCT-013-030 (30A/1V)
• 10µF capacitor
• 2 resistors (between 10k-470kΩ)

Other requirements:

• AWS Account (Should be able to run in free-tier)
• Install PlatformIO on your system
• Drivers for your ESP32 board

Read my blog post for more instructions: https://savjee.be/2019/07/Home-Energy-Monitor-ESP32-CT-Sensor-Emonlib/

Contribute

I'm happy to merge in any pull requests. Also feel free to report bugs or feature requests.