Renewable Resources

Hydroelectric Power: Analysis, Benefits, and Drawbacks
Student’s NameInstitutional Affiliation
Abstract
Hydroelectric power plants generate electricity by harnessing the kinetic energy of moving water and converting it to electrical energy. Hydroelectric energy is renewable since the sun powers the hydrologic cycle that in turn causes surface runoff. The runoff, when collected in a dam or reservoir, contains kinetic energy that turns turbines, which in turn produce electricity. Hydroelectric energy is efficient because the hydropower plant converts 90% of the total available energy into electricity contrary to fossil fuel plants that only convert 50%. Hydroelectric energy is also inexpensive since it uses water, a natural resource. However, the dams constructed as water reservoirs cause flooding in the downstream areas. They also prevent fish from moving upstream to spawn. The amount of electrical energy (in megawatts) generated by a hydropower plant depends on the distance through which the water flows and the flow rate. This paper examines the harnessing of hydroelectric energy as well as its benefits and drawbacks.
Hydroelectric Power: Analysis, Benefits, and Drawbacks
According to DIBR (2005), hydroelectric power is renewable energy harnessed from moving water. Before the generator can produce electric energy in a hydropower station, solar energy powers the hydrologic cycle that in turn leads to surface runoff. The runoff from melting snow or rain eventually reaches the reservoir or dam.

Before generating energy, the water must be in motion. The moving water provides kinetic energy that in turn moves turbines creating mechanical energy. The turbines turn a generator rotor that converts mechanical energy into electrical energy. Because hydroelectric power plants use water, they are located on canals, streams, and rivers. In order to ensure reliable water supply, a dam is necessary to store water.
On average, a hydropower plant generates 90% of the total available energy into electricity. The theoretical horsepower (THP) provides a measure of the mechanical energy produced by a power plant. It depends on the flow rate (cubic feet per second), the head in feet, and a constant (8.8). Multiplying THP by 746 gives the total electrical power generated by the hydropower station (DIBR, 2005). The amount of electrical energy in megawatts produced by a power station in a year depends on the head or vertical distance through which the water flows and the flow rate. Hoover Dam, for instance, produces 4 billion kilowatt-hours of electrical energy every year (DIBR, 2017). The 24/7 power availability and zero carbon emissions are the two main benefits of hydropower. Hydroelectric power is also efficient and inexpensive. On the other hand, the drawbacks of hydropower include flooding on the downstream areas of the dam, altered amounts of quality water that reaches downstream regions and preventing fish from migrating upstream to spawn.
References
U.S. Department of the Interior Bureau of Reclamation (DIBR). (2005). Hydroelectric Power. Reclamation-Managing Water in the West. Retrieved from: https://www.usbr.gov/power/edu/pamphlet.pdfU.S. Department of the Interior Bureau of Reclamation (DIBR). (2017). Hoover Dam. Reclamation-Managing Water in the West. Retrieved from: https://www.usbr.gov/lc/hooverdam/faqs/powerfaq.html