The energy transition, with massive electrification of uses and a strong penetration of renewable energies, could put electrical networks under stress. This Zenon Research report (in French) provides an overview of the current situation and challenges of electrical networks, the backbone of the energy transition, and explores developing technologies for the transmission and distribution of electricity. It investigates the balance between supply and demand in the age of variable energies, presents some technological solutions and provides an overview of the main obstacles that the evolution of networks could encounter.