Hydro-electric power (or hydroelectricity) refers to the process of generating electricity from flowing water. As water flows downstream, it spins a turbine that generates electricity. It is considered a renewable resource, because the water cycle ensures that water will constantly flow through an ecosystem. Hydro-power is one of the US’s largest sources of renewable energy, at 6.5% of electricity production. In Texas, however, hydroelectricity doesn’t even reach the 1% mark.
Although hydro-power is an extremely low-cost and reliable option (as opposed to intermittent source of energy like solar and wind), it often requires a favorable geographic location to be installed. For one, fast-moving water sources (mostly rivers) are necessary, something that isn’t always as freely available in Texas as in other states. Three main types of hydroelectric power plants are used in the US:
- Impoundment Facilities use a dam to create a large body of water. As the water flows downstream, it turns a turbine, which generates electricity.
- Pumped Storage Facilities are similar to impoundment facilities, in that they use a dam to store water at a higher elevation. Pumped storage plants also have a second body of water below the dam. Water can be pumped from the below the dam to above it, storing energy for later use.
- Run-of-the-river Facilities rely on natural water flow to spin a turbine and generate electricity. These may use dams.
Hydroelectric facilities can also be classified by their sizes, which you can read more about here.
While hydro-electricity is cheap and clean, the dams themselves can create unintentional ecological consequences, particularly in the local area. Dam failures can also result in flooding the downstream areas. As such, dams generally must assess how construction will impact nearby towns and wildlife.