No Consumer Electronic device is Ideal. That is, some electrical energy is lost in the form of dissipation (like eddy current loss, joules heating loss, hysteresis etc.) Similarly, devices also lose energy while idling. That is, on standby mode. In technical terms, this is also called No Load Power, Vampire Power, Phantom Load or Leaking electricity.

If there is no current flowing in the secondary side , there is no de-magnetising flux generated that means there is no need to draw more current from the source . So primary current would contain only the exciting current (i.e. 'NO LOAD CURRENT').

On a macroscopic scale, such taken for granted tiny idling load accounts for enormous power wastage over time.
Download 'client-module.zip' (from this repository)
Extract 'client-module.zip'
Change Directory to the path of the Client-Module in Terminal
cd path/to/client-module
Change Permissions to make it executable
sudo chmod +x linux.sh
RUN the script
./linux.sh
Power-Pi also has an android mobile application (PowerPi.apk) which has been developed keeping in mind the need to visualize the entire process. It facilitates the user to see how much energy his Power-Pi setup is saving. Additionaly, the same app can also be doubled up as a home automation interface working on top of the same Power-Pi setup. The app is made with React Native.

Note: Actual saving depends on vampire load of machine(s).