The primary use of hydropower energy is to produce electricity. There are three types of hydropower facilities:

  • Impoundment facilities – These are typically large hydropower systems that use a dam to store river water in a reservoir.
  • Diversion facilities – Also called run-of-river, this type of facility channels a portion of a river through a canal or penstock; it may not require the use of a dam.
  • Pumped storage – Pumped storage facilities store the electricity generated by other power sources (such as solar, wind, and nuclear) for later use. It stores energy by pumping water uphill to a reservoir at higher elevation from a second reservoir at a lower elevation. During periods of high electricity demand, the water is released back to the lower reservoir, turning a turbine and generating electricity.[1]

Hydroelectric power plants are also categorized as micro hydropower, small hydropower, and large hydropower plants. Small systems could be suitable for providing power to a home or village, while large projects are capable of producing electricity for utilities.

  • Micro hydropower – A micro hydropower plant has a capacity up to 100 kilowatts. A small or micro hydropower system can produce enough electricity for a home, farm, ranch, or village.
  • Small hydropower – The Department of Energy defines small hydropower as projects that generate between 100 kilowatts and 10MW..
  • Large hydropower – The Department of Energy defines large hydropower as facilities that have a capacity of more than 30 MW.[2]

The US Energy Information Administration (EIA) provides insight into renewable energy consumption for electricity generation by energy use sector and energy source. In the EIA’s Electric Power Annual 2020  report (released in  March 2022), Table 3.14 Utility Scale Facility Net Generation from Hydroelectric (Conventional) Power outlines the number of megawatt hours generated at utility scale hydropower facilities. This table includes information for all sectors, the electric power sector (which is further segmented to include electric utilities and independent power producers), the commercial sector, and the industrial sector.

Source: US Energy Information Administration, 2022[3]

Updated by Erin Bennett, June 2022