Renewable Energy Review: Hydroelectric

What is it? Hydroelectricity is produced from hydropower, which is derived from the energy of falling or fast-moving water. It is produced in 150 countries and, in 2015, produced nearly 17% of the world’s total electricity. It also produced around 70% of all renewable electricity. Hydroelectricity’s low cost makes it a competitive source of renewable electricity; the power plants consume no water, and the project produces no direct waste and has a considerably lower output level of greenhouse gasses than fossil fuel energy plants..


How is it sourced? The most popular form of harnessing hydroelectric power is by capturing the kinetic energy of flowing rivers. This is done through the utilization of a series of dams, which are constructed to store water in a reservoir. When released the water flows through turbines, producing electricity. The water is cycled between lower and upper reservoirs to control electricity generation. Hydroelectric power can also be harnessed through “run-of-river hydropower.” In this method, a portion of a river is funneled through a channel, thus eliminating the need for a dam.


How is it used? Though the use of hydroelectric power is dependent on geographic location, it is used to supply electricity in a variety of situations—from farm and ranch operations to individual buildings and towns.


Are there any downsides? There are some minor environmental consequences associated with the use of hydropower. Interventions in waterways, such as damming and changing flow, can impact the habitat of thousands of species. Additionally, building the plants themselves is an expensive project, and widespread droughts are likely to exponentially increase the cost of hydroelectric power.