Meter boxes allow you to measure the complete electricity and/or fuel consumption & prodcution production over multiple base circuits, over multiple canvasses, and if desired over a full model.

Library

The electricty meterbox and fuel meterbox can be found in the Control library

...

Assigning

Base Circuits

You can assign any base circuit that produces or consumes electricity to an electricity meter. Idem for fuel.
Assinging and unassigning can be done using the buttons in the menu bar:

...

Additional consumption and production