Electricity Saving using Smart Home Monitoring

There is a lot of electricity loss caused when we accidentally keep the lights, fans, AC or any other daily appliance of our home ON. This is a common scenario and leads to a massive electricity loss of a whole city is considered for example. So, what my project does it that the Walabot sensor continuously monitors the room for any human presence it, and when it senses no human presence in the room, it sends this data to the raspberry pi which is connected to my mobile app through the internet. Now the pi will send this information to the app which will then give a notification on the user's phone stating that which appliances are on.