What to Know About Hydropower
Hydropower, also known as hydroelectric power, stands as one of the earliest and most substantial sources of renewable energy, utilizing the natural flow of water to generate electricity. This age-old energy source constitutes 28.7% of total U.S. renewable electricity generation and contributes about 6.2% to U.S. electricity generation overall.
Contrary to the common association of hydropower with colossal structures like the Hoover Dam, hydropower facilities exhibit a broad range of sizes. While some are extensive, tapping into entire rivers, others are diminutive, harnessing water flows in municipal facilities or irrigation channels. Some facilities even operate without dams, employing diversions or run-of-river systems that guide a portion of a stream through a powerhouse. Remarkably, hydropower's ubiquity extends far beyond popular perception, with all states, except Delaware and Mississippi, utilizing it for electricity. Washington, for instance, relied on hydropower for a substantial 66% of its electricity in 2020.
Hydropower technologies capitalize on the elevation difference created by dam or diversion structures, utilizing the flow of water from a higher to a lower point to generate power.
Hydropower hinges on the water cycle, a process crucial for comprehending its functioning. The water cycle involves three key stages:
Solar Heating: Solar energy heats water on surfaces like rivers, lakes, and oceans, causing evaporation.
Condensation and Precipitation: Water vapor condenses into clouds, leading to precipitation in the form of rain or snow.
Collection and Renewal: Precipitation gathers in streams and rivers, eventually flowing back to oceans and lakes, completing the cycle.
Understanding precipitation in a region is vital for hydropower, with seasonal and long-term changes impacting its availability.
Hydropower plants are strategically located based on water sources, leveraging water flow and elevation changes for optimal energy production. In these plants, water moves through turbines powered by the force of the river or stored water, generating electricity. Conventional facilities encompass run-of-the-river and storage systems, while pumped-storage facilities manage electricity demand fluctuations by pumping water to higher elevations during low-demand periods and releasing it during peak demand, despite having a net negative electricity generation balance.
Recognized as an economical electricity source, hydropower boasts costs lower than many alternatives. States predominantly reliant on hydropower, such as Idaho, Washington, and Oregon, benefit from lower energy bills. Despite significant initial costs, the extended lifespan of hydropower facilities ensures that these expenses are spread across time. The extended operational periods of hydropower equipment further contribute to long-term cost savings.
Installation costs for large hydropower facilities primarily comprise civil construction works and electromechanical equipment costs. The specificity of hydropower technology allows for cost minimization through careful site selection and design. Beyond its role in electricity generation, hydropower brings additional benefits, including flood control, support for irrigation, and a stable water supply.
