1. Hydraulics

Electrical power generation began to develop at the end of the 19th century, and was rapidly organized into networks, the aim being to make this resource, produced by centralized plants using hydraulic power and fossil fuels, available to as many people as possible. Against this backdrop, and with the technological means available at the time, alternating current (AC) transmission rapidly became the norm. The unit power of generating plants grew steadily until, in the 1980s, they reached values in excess of one gigawatt.

The end of the twentieth century saw two important developments. On the one hand, autonomous or "off-grid" power generation was offered to consumers who did not have access to the grid (rural areas in developing countries) or for those who were far from it and for whom the...