Résumé en anglais

This paper is a synthesis of our research work during the fourth "SEME" (Week of Mathematical Studies for Firms) in Institut Henri Poincaré, Paris. We are grateful to the organizers of the week and to Gilles Perrin (AREVA) who suggested the topic. The goal was to come up with a method to target as precisely as possible an expected energy consumption curve under technological constraints (e.g. the fact that machines can not switch too quickly between different productivity levels, or may need a minimal amount of time to be restarted should their production reach zero at some point). Inthis paper we describe two approaches : the first one is inspired from optimal control theory while the second one relies on convex analysis.