What is energy? Why is it one of the key issues for tomorrow's society?

We will discuss the notion of energy in physics and show that energy can take different forms. We will illustrate, using simple experiments, the conversions from one form of energy to another. In particular, electricity is an essential form of energy for human activity today: we will show how to produce it from other forms of energy: we will explain the principle of the battery and the electric motor (or alternator). Finally, we will discuss the primary energies used in the world: which energy sources can be considered renewable? What are the consequences of their use on the climate?

Examples of experiences

Conversion of solar radiation into propeller motion
Hot air engine (Stirling) whose rotation generates electricity.