Glossary
Dams
Large barriers built across rivers to impound water, creating a reservoir and controlling water flow for various purposes, including hydroelectric power generation.
Example:
The construction of a new dam can provide flood control and a reliable water supply for agriculture in arid regions.
Economic Considerations (of hydropower)
The financial costs and benefits associated with building, operating, and maintaining hydropower infrastructure, including energy production value and construction expenses.
Example:
The long-term economic considerations of a hydropower plant include its operational lifespan and the stable electricity prices it can offer.
Environmental Impacts (of hydropower)
The effects, both positive and negative, that hydroelectric power generation has on ecosystems, natural resources, and the surrounding environment.
Example:
Assessing the environmental impacts of a proposed hydropower project involves evaluating potential changes to river ecosystems and local biodiversity.
Fish Ladders
Structures built to help fish bypass dams and other obstructions, allowing them to continue their upstream migration.
Example:
To mitigate the impact on aquatic life, many modern dams incorporate fish ladders to assist salmon and other migratory species.
Fish Migration Patterns
The seasonal or life-stage movements of fish species, which can be disrupted by dams that block their natural routes to spawning or feeding grounds.
Example:
Dams can severely impact fish migration patterns, preventing species like salmon from reaching their ancestral spawning areas upstream.
Fossil Fuels
Non-renewable energy sources formed from the remains of ancient organisms over millions of years, including coal, oil, and natural gas.
Example:
Burning fossil fuels for energy releases significant amounts of greenhouse gases, contributing to global warming.
Generator
A device that converts mechanical energy into electrical energy, typically by rotating a coil within a magnetic field.
Example:
The spinning turbine is directly connected to a generator, which then produces the usable electricity that powers our homes.
Grand Coulee Dam
A gravity dam on the Columbia River in Washington, notable as the largest hydropower producer in the United States.
Example:
The immense power generated by the Grand Coulee Dam supports a vast agricultural region and numerous industries.
Greenhouse Gas Emissions (from reservoirs)
The release of gases like methane and carbon dioxide from decaying organic matter in flooded reservoir areas, contributing to climate change.
Example:
While often considered clean, some hydropower projects can lead to greenhouse gas emissions from reservoirs, especially in tropical regions.
Habitat Disruption
The alteration or destruction of natural habitats, often due to human activities like dam construction, leading to displacement or loss of species.
Example:
The creation of a large reservoir can cause significant habitat disruption, submerging forests and displacing terrestrial wildlife.
Hoover Dam
A concrete arch-gravity dam in the Black Canyon of the Colorado River, known for providing flood control, irrigation, domestic water, and hydroelectric power.
Example:
The Hoover Dam is a monumental engineering feat that transformed the American Southwest by providing essential resources.
Hydropower
A renewable energy source that generates electricity by harnessing the kinetic energy of moving water, typically through the use of turbines.
Example:
Many countries rely on hydropower from large rivers to meet a significant portion of their electricity demands.
Kinetic Energy
The energy an object possesses due to its motion. In hydropower, it refers to the energy of moving water.
Example:
As water rushes down a steep incline, its kinetic energy increases dramatically, making it ideal for turning turbines.
Renewable Energy
Energy derived from natural processes that are replenished constantly, such as solar, wind, hydro, and geothermal power.
Example:
Shifting towards renewable energy sources like hydropower is crucial for reducing our reliance on fossil fuels and mitigating climate change.
Reservoir
An artificial lake created by a dam, used to store water for various purposes such as drinking water, irrigation, and hydroelectric power generation.
Example:
The vast reservoir behind the dam provides a crucial water source for millions of people and supports local recreational activities.
Sedimentation
The process by which sediment (like silt, sand, and gravel) is deposited, often accumulating behind dams and reducing reservoir capacity and altering downstream riverbeds.
Example:
Over time, sedimentation behind a dam can reduce the reservoir's storage volume and necessitate costly dredging operations.
Three Gorges Dam
The world's largest power station in terms of installed capacity, located on the Yangtze River in China, providing flood control and power but also causing significant environmental and social impacts.
Example:
Despite its massive power output, the Three Gorges Dam faced criticism for its role in displacing millions and altering river ecosystems.
Tidal Waves
A method of hydropower that captures the energy from the rise and fall of ocean tides to generate electricity.
Example:
A coastal power plant might utilize the predictable ebb and flow of tidal waves to generate clean energy for nearby communities.
Turbines
Mechanical devices with blades that are rotated by a fluid (like water or steam) to convert the fluid's kinetic energy into mechanical energy, which then drives a generator.
Example:
The powerful flow of water through a dam spins the massive turbines, initiating the electricity generation process.
Water Quality Changes
Alterations in the physical, chemical, or biological characteristics of water, which can be influenced by dam construction and reservoir formation.
Example:
Reduced oxygen levels and altered temperature stratification in a reservoir can lead to negative water quality changes downstream.