1. Power system energy balance: scope, indicators and challenges

1.1 Definition of energy balance

As with any physical system, an energy balance involves defining a study area, taking stock of energy flows and differentiating between incoming and outgoing flows.

In a study area (the physical system), centralized producers (power plants connected to transmission networks) or decentralized producers (connected to distribution networks) inject energy into the network at each time step (incoming flows).

In the case of a transmission company, this energy is injected at power stations and delivered to a few large customers and to the source substations of electrical distribution companies. Entry and exit points are few and far between.

In the case of an electricity distribution company...