Hydropower - Regulation
Pumped Storage Hydroelectric Projects
Pumped-storage projects differ from conventional hydroelectric projects.
They normally pump water from a lower reservoir to an upper reservoir
when demand for electricity is low. Water is stored in an upper
reservoir for release to generate power during periods of peak demand.
For example, in the summer water is released during the day for
generating power to satisfy the high demand for electricity for
air conditioning. At night, when demand decreases, the water is
pumped back to the upper reservoir for use the next day.
These projects are uniquely suited for generating power when demand
for electricity is high and for supplying reserve capacity to complement
the output of large fossil-fueled and nuclear steam-electric plants.
Start-up of this type of project is almost immediate, thus serving
peak demand for power better than fossil-fueled plants that require
significantly more start-up time. Like conventional projects, they
use falling water to generate power, but they use reversible turbines
to pump the water back to the upper reservoir. This type of project
is particularly effective at sites having high heads (large differences
in elevation between the upper and lower reservoir).
| State Project |
Name |
Capacity |
Head |
Owner |
| California |
Helms |
1,050 MW |
1,630 feet |
PG&E Company |
| Virginia |
Bath County |
|
|
VEPCO |
The 1,050-megawatt Helms pumped-storage project, operated by Pacific
Gas and Electric Company in Fresno County, California, has a head
of 1,630 feet - the highest in the United States. The largest operating,
privately owned pumped storage-project is jointly owned by Virginia
Electric and Power Company and Allegheny Generating Company in Bath
County, Virginia. In addition, the largest non-federal, publicly
owned pumped-storage project is part of the California Aqueduct
Project and has a capacity of 1,275 megawatts. It is operated by
the City of Los Angeles. The largest federally owned pumped storage
project is the Tennessee Valley Authority's 1,530-megawatt Raccoon
Mountain project on the Tennessee River in Tennessee.
|
 |
|
