{"id":1833,"date":"2017-05-07T14:33:17","date_gmt":"2017-05-07T13:33:17","guid":{"rendered":"https:\/\/www.nathankowald.com\/blog\/?p=1833"},"modified":"2017-05-07T14:34:36","modified_gmt":"2017-05-07T13:34:36","slug":"raspberry-pi-prepaid-energy-monitor","status":"publish","type":"post","link":"https:\/\/www.nathankowald.com\/blog\/2017\/05\/raspberry-pi-prepaid-energy-monitor\/","title":{"rendered":"Prepaid energy monitor with a Raspberry Pi"},"content":{"rendered":"

Instructions: https:\/\/github.com\/n8kowald\/powerpi<\/a><\/h4>\n

My flat has a prepayment energy meter.
\nSometimes I forget to check how much money we have and the power goes out, forcing me to walk to the nearest open PayPoint location at inconvenient times.<\/p>\n

I wanted a way to automate these checks.<\/p>\n

\"\"

The Raspberry Pi B+ enclosed emails me a photo of the money we have left<\/p><\/div>\n

I had an unused Raspberry Pi B+, camera module (REV 1.3), and a USB Wi-Fi dongle. With these I could take a photo of the amount left and email myself a photo every day at a specified time.<\/p>\n

It turned out to be easy.
\nThe most time consuming bit was experimenting with raspistill<\/a> options to produce the best photo for the dark cabinet it’s enclosed in.<\/p>\n

\"Amount

Amount of money left on our prepaid electricity meter<\/p><\/div>\n

As you can see the photo is not amazing. However, considering it was taken in a dark cabinet I’m happy with the result.<\/p>\n

Full instructions here: https:\/\/github.com\/n8kowald\/powerpi<\/a><\/h4>\n

Next, I want to use Optical Character Recognition (OCR) to detect the amount in the photo.
\nI could then take readings every 5 minutes, save that to a database and produce a graph of the times when we use the most electricity.<\/p>\n","protected":false},"excerpt":{"rendered":"

Instructions: https:\/\/github.com\/n8kowald\/powerpi My flat has a prepayment energy meter. Sometimes I forget to check how much money we have and the power goes out, forcing me to walk to the nearest open PayPoint location at inconvenient times. I wanted a way to automate these checks. I had an unused Raspberry Pi B+, camera module (REV […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[25],"tags":[],"class_list":["post-1833","post","type-post","status-publish","format-standard","hentry","category-raspberry-pi"],"acf":[],"aioseo_notices":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t