[Afonso] picked up a cheap energy use monitor a few years back ... He set out to reverse engineer the wireless protocol in order to extend the use of the system. As the name of this column ...

Converting the radio transmissions in the air into power. All wireless signals comprise energy and data, the latter derived by the way the radio waves are modulated. Wireless energy harvesting ...

Luckily, as [Xavier Decuyper] explains, you can build a very robust DIY energy monitoring system without having to modify your AC wiring. In the video after the break, [Xavier] goes over the ...