Monitoring your home’s energy use is the best way to get a handle on your utility bills. After all, you can’t manage what you can’t measure! The only problem is that most home energy monitoring systems are cumbersome, complicated, or expensive. At least, until now. [Kevin] has created a new electricity meter based on Particle Photons which should alleviate all of these problems.
The Particle Photon (we get confused on the naming scheme but believe this the new version of what used to be called the Spark Core) is a WiFi-enabled development board. [Kevin] is using two, one to drive the display and one to monitor the electricity usage. This part is simple enough, each watt-hour is accompanied by a pulse of an LED on the meter which is picked up by a TLS257 light-to-voltage sensor. The display is a Nextion TFT HMI (touch screen) which is pretty well suited for this application. The data is corralled by emoncms, part of the OpenEnergyMonitor platform, which ties everything together.
For a project that has been done more than a few times, this one does a great job of keeping the price down while maintaining a great aesthetic. Make sure to check out the video below to see it in action.
The project looks very good but in England electric is easy to monitor the problem is gas and this now is the most expensive product that we use so will you be adding gas to your project?
I would love to but I have the same ancient gas meter in this project.
http://hackaday.com/2015/06/30/disassembled-mouse-keeps-track-of-gas-meter/
As the meter is outside I don’t really want the cabinet to light up bright green and attract unwanted attention. I’m still looking at ways to do it.
Webcam and OCR?
saw this way back https://stackoverflow.com/questions/12607730/how-to-ocr-pictures-of-my-electric-meter
links in the comments too on another similar project
Don’t be so sure about 0.1 precision of DHT22, just place 5 of them on the breadboard and make basic interface, you will see funny numbers.
About problem with light sensor registering door opening, implement simple high-pass filter to register only led blinks and ignore ambient light change.
For my meter I used a simple photoresistor with a 100kohm pullup (actually 6 of them, because of 3 meters giving out also the reactive power). To shield it from ambient light i put it in a 5 cm long piece of straw wrapped in black duct tape. Worked flawlessly for months with no filtering.
The network device was a 14 euros dlink dir-300 running openwrt and a custom lua webserver receiving serial readings from an atmega and delievering graphs and instant updates thanks to long held http requests, but now i would redo it with a single esp8266 and websockets.
I use SI7022, a bit more difficult to solder, but it has a good price with mouser and i trust it more than ebay stuff.
Actually the company renamed from Spark to Particle, and the Photon is the next generation of the Core; both are still sold.
Does this universally work will all meters? Potential for a CT option?
some smart meters have an led that blinks once per watt hour, this is the signal that he is using for measurement.
Surprised that no one has mentioned the Nextion’s awesomeness here! This little guy, originally an Indiegogo, has a really nice crisp display, and it updates pretty fast – something that you usually *don’t* see with Arduino displays. The fact that it’s already being used in public is a good sign that this thing really works! (I have one that I haven’t gotten to using yet…)
I wonder how much electricity the world would save if all the smart meters were turned off?
The fantastic GUI is what turns this from a hack into a viable product.