Hydroelectric Energy: An Ancestral and Modern Energy Source

The use of water as an energy source has a long, rich history. From the 18th-century mill in Cromford, England, to the monumental Three Gorges Dam in China, human ingenuity in harnessing water power has been essential.

The ancient Romans and Greeks used water wheels to mill grain, but Hydroelectric Energy owes much of its development to British civil engineer John Smeaton, who first built large cast-iron water wheels.

This form of energy played a significant role during the Industrial Revolution, powering textile, leather, and machine-building industries in the early 19th century and helping the growth of new industrial cities in Europe and America.

Water is vital for life and food production and is also one of the most effective renewable energy sources.

What is Hydroelectric Energy, and how does it work?

Hydroelectric Energy is based on harnessing the power of moving water. Its generation depends on two essential elements: the available water flow and the height difference through which the water is released. Hydroelectric Energy plants use gravity to accelerate water and release its potential energy.

For example, water stored in a reservoir is directed to a turbine through pipes, where its kinetic energy is transformed into mechanical energy as the water rotates the turbine.

The turbine is a crucial component of a hydroelectric plant, and its design can vary depending on the specific characteristics of the water flow and the height difference.

The mechanical energy produced is then converted into electricity by an electric al generator. The electricity is sent to transformers to increase its voltage for efficient transmission and distribution through the electrical grid.

Hydroelectric plants' excellent performance is due to their high energy conversion efficiency and flexibility in adapting to and leveraging the global energy transition and subsequent changes in electricity markets. Consistent with these characteristics, the five largest renewable energy plants in the world in terms of capacity and production are powered by water.

Hydroelectric Energy in the National Electric System

According to the National Electric Coordinator (CEN), as of May 2024, the installed capacity of hydroelectric plants in the National Electric System is around 7,500 MW, representing approximately 21% of the country’s total installed capacity. According to the Ministry of Energy's basin study, Chile has a Hydroelectric Energy potential of around 16,000 MW.

Types of hydroelectric plants in Chile

Enel operates two types of Hydroelectric Energy plants in Chile, adapted to the country’s geographical and climatic characteristics. These are:

Reservoir Plants: These plants store large volumes of water in reservoirs, allowing for flow regulation and ensuring production in line with the national electric system and market needs. These plants include Rapel, Cipreses, Pehuenche, El Toro, Ralco, and Pangue.
Run-of-River Plants: These plants take advantage of the continuous flow of rivers without incorporating large reservoirs, generating electricity steadily with minimal impact on the natural environment. These plants include Los Molles, Sauzal, Sauzalito, Isla, Ojos de Agua, Curillinque, Loma Alta, Abanico, Antuco, Palmucho, Pullinque, and Pilmaiquén.

Innovation and efficiency at Enel

At Enel, we operate hydroelectric plants with advanced technologies that allow us to maximize water's energy potential. These plants achieve exceptional performance and contribute significantly to the generation of clean energy in Chile.

Our hydroelectric plants are an integral part of our strategy to lead the energy transition toward a more sustainable future. They generate renewable energy and reduce carbon emissions.