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California Hydroelectric Statistics & Data

photo of Hyatt Power Plant at Oroville Dam
Photo by California Department of Water Resources

In 2007, hydro-produced electricity used by California totaled nearly 43,625 gigawatt-hours (GWh) or 14.5 percent of the state's total system power. In-state production accounted for 69.5% of all hydroelectricity, while imports from other states totaled 30.5%.

A total of 343 hydroelectric facilities are in California with an installed capacity of 13,057 megawatts (MW). Hydro facilities are broken down into two categories: larger than 30 MW capacity are called "large hydro"; smaller than 30 MW capacity is considered "small hydro" and are totalled into the renewable energy portfolio standards. The amount of hydroelectricity produced varies each year. It is largely dependent on rainfall.

One of those hydro facilities is the Edward Hyatt Power Plant on Oroville Dam, pictured on the right. According to the Calif. Dept. of Water Resources, the "Hyatt Power Plant was constructed in the bedrock below Lake Oroville. A cavern the size of two football fields was dug out to house the facility." Of the six units, three generate power, while the other three can either pump water for pumped water storage or generate power."

The Hyatt Power Plant is part of California's State Water Project, which is the largest state-built water and power development and conveyance system in the United States. It is the largest single power consumer in the state and the fourth largest energy producer. It makes a significant contribution to the state's electrical grid because the hydro power offers a flexible resource with rapid response to help stabilize the power grid.


California 2007 Total System Power from Hydro in Gigawatt Hours

Fuel Type In-State Generation Northwest Imports Southwest Imports Total System Power Percent of Total System Power
Large Hydro 23,283 9,263 2,686 35,232 11.7%
Small Hydro 3,675 4,700 18 8,393 2.8%
Total Generation 209,856 24,669 67,547 302,072 100.0%

Source: Total System Power

 

Total Hydroelectricity Production
(In Gigawatt-Hours; Includes Imports)


1983 1984 1985 1986 1987 1988 1989
Hydroelectric 59,351 46,880 33,898 44,478 27,140 26,692 32,742
Total Generation 199,609 211,900 210,172 211,028 220,371 232,926 238,567
 
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999
Hydroelectric 26,092 23,244 22,373 41,595 25,626 51,665 47,883 41,400 48,757 41,627
Total Generation 252,355 242,343 245,535 242,026 256,719 256,367 253,621 255,080 276,412 275,803
 
2000 2001 2002 2003 2004 2005 2006 2007
Hydroelectric 42,053 25,005 31,221 36,140 34,372 39,891 48,431 43,625
Total Generation 280,496 265,059 272,509 276,969 289,359 287,977 295,268 302,072


graph showing hydro generation from 1983-2007