Hydroelectric Power M. Clark, S. Smith, K. Mazzone, M. Mancuso

Thermodynamics – Prof. Jill Johnson, Prof. Sean Nowling

Drawbacks A dam disrupts air flow within a river system which disrupts the entire ecosystem by creating an imbalance. In order to have an effective hydro station a large reservoir has to be built. Building a large reservoir requires large amounts of money and time and also the approval of local residents. During drought or dry seasons, the water levels in the reservoir may decrease, which would effect electrical output. Dams are at a high risk of failure no matter how well built. More than 650 dams have been removed in the US, in part to improve habitats but also because some dams have become unsafe.

Tidal power plants A high-capacity dam is built across a partly enclosed coastal body of water to hold back the water at high tide. At low tide, water channel gates in the dam are opened to release a cascade of water which drives a turbine to generate electricity.

Introduction Hydroelectric power (or water power) is energy derived from the use of falling and running water, which may be harnessed for useful purposes. In the past, flowing water turned waterwheels of mills to grind grain. In the 21st century, hydropower plants convert the energy of flowing water into mechanical energy, turning turbines to create electricity. A dam creates a height from which water can flow at a fast rate. When it reaches the power plant, it pushes the turbine blades attached to the electrical generator. The amount of generated electricity depends on the volume of the water flow and the height difference between the reservoir surface and the turbines at the bottom.

Versatility According to BP, hydroelectricity is the third most commonly used energy source in the world. It is the most used renewable energy source.

Hydropower remains the only means of storing large quantities of energy for almost instantaneous use. Water is held in a large reservoir behind a dam, with a hydroelectric power plant below. Whenever power is needed, the water valves are opened, the moving water spins the turbines, and the generator quickly produces electricity.

References 1. www.bp.com

2. Cothran, Daniel. Opposing Viewpoints: Energy Alternatives. San Diego,CA: Greenhaven Press, 2002.

3. Botkin, Daniel. Powering the Future. Upper Saddle River, NJ: Pearson Education, Inc., 2010.

4. Alters, Sandra. Energy: Supplies, Sustainability, and Costs. Farmington Hills, MI: Gale, 2009.