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Water-Energy Nexus

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In the figure at left, many water-energy connections are shown; blue bubbles highlight where water is used to generate energy and orange bubbles highlight where energy is used in the water use cycle. The two bubbles on the far right side of the figure outlined in green show where energy is expended to extract and convey water. Detailed energy intensity for extraction and conveyance of many regional water supplies are to be found here. Please click on image for detailed view.












The pie chart at right depicts how energy is used in California’s water sector.  California uses about 2,500 million megawatt-hours (MWh) of energy per year. That’s enough energy to drive around the Earth over 75 million times!  About 12% of that energy use is related to water use. Energy is used by the water sector to extract (pump it from the ground), convey (move it through pipes and sometimes over mountains), treat (clean it to make it drinkable), and condition (heat and chill) water. The majority of that energy comes from electricity and non-power plant natural gas, and a very small amount comes from crude oil. End uses of water (like residential hot water heaters) constitute about 10% of the state's energy use. Extraction, conveyance, and treatment constitute the other 2% (CEC, 2013CEC, 2005CPUC, 2010 and 2011). This graphic highlights the importance of water use habits of residential, commercial, and industrial users. Please click on image for a detailed view.



Energy Use Related to Water - This is an update to the figure found in California Water Plan 2013 Highlights and Volume 1.




Hydroelectricity in California

California has over 250 hydroelectric generating plants. Hydroelectricity provides California with about 12% of its electricity (about 3% of total energy) each year. However, hydroelectric generation varies greatly from year to year depending on hydrology. In dry years hydroelectric generation may drop by as much as 25%.

For more statewide water-energy nexus information please see Volume 1 of the California Water Plan Update 2013- California Water Today.