PiMeter

Smart energy meter for Raspberry PI

This projects has everything you need to start monitoring and recording your electric energy usage with a Raspberry PI and Arduino. You get easy access to a mobile-friendly daily graph and all-time stats.

It is completely non-intrusive and works by watching the blinks given out by a house-hold electric meter. Each blink of the supplier’s meter will represent 0.001kWh of energy usage. We use a cheap Arduino nano (clone or genuine) to monitor blnks, then a Raspberry PI runs a rich web interface with daily graphs showing peaks and troughs.

Mobile energy meter

Requirements

An Arduino with LDR connected and USB cable
A Raspberry PI
An electric meter which has a blinking LED to indicate current consumption

Installation on Arduino

Open the arduino/flasher.ino sketch in the Arduino IDE
Select your device and flash the code.
Install LDR and signal LED to correct pins as per the sketch.

Installation for Raspberry PI

Clone the repository and then install the software:

npm install bower -g
npm install
bower install

If your Raspberry PI has less than 512MB RAM you may want to enable a swapfile due to memory needed when building SQLite

node app starts the program, navigate to http://localhost/ or the IP address of the PI.
Initialize the empty energy DB with the following command: sqlite3 energy.db < provision.sql

Running the software

Flash your Arduino with the software and attach its LDR to the blinking LED on your energy meter.
On boot-up start the meter/meter.py program. This will then start logging data from the Arduino.

I have run this system at my own house for over a year and have had no issues to speak of. It has been interesting to monitor the usage of various appliances and what causes a peak and what my daily usage is like.