A smart electrical outlet that allows customers to rent electricity by paying with Bitcoins.

Project Idea
Bitcoin and blockchain technology opened a whole lot of opportunities for paying for goods and services but the catch was that it wasn’t fully automated because it lacked easy hardware integration support. However, it got easier with the release of the Koyn library. In short, the Koyn library allows your hardware like Arduino compatible boards to receive and send Bitcoin payments.

One application model for Bitcoin that interests me is pay per service, and one of many applications I decided to get my hands dirty on is renting electricity. So, I started building an electrical outlet that is powered by Bitcoin.

Disclaimer
This project works on HIGH AC voltage which is quite dangerous. Your safety is your own responsibility, including proper use of equipment and safety gear, and determining whether you have adequate skill and experience. You must accept that you and you alone are responsible for your safety and the safety of others if you choose to build this project.

Brainstorming & Sketching
After deciding to get my hands dirty, it was time to sit down and write down how the device would work and what the sketch would look like.

The device will work in this process:

Power up
Connect to Internet and sync to the Bitcoin network
Listen for incoming transactions for its Bitcoin address
If payment is received, calculate the capacity of electrical energy purchased
Give access to electrical energy through the device’s outlets
Pressing a push button twice will end the current session and return the change (if found) to the payee’s address
After consuming, the purchased quota the device will end the session
The device will also include a 16 x 2 LCD to show its status.”

Link