Add: ->>In 2014, DWR completed several analyses of energy used in California’s water sector and launched its water-energy nexus webpage  hyperlink to page Add: Water-Energy Nexus to side navigation bar

Water-Energy Nexus Water and energy have typically been managed separately despite the important links between the two. As shown in the graphic below, water is used in the production of nearly every major energy source. Likewise, energy is used in multiple ways and at multiple steps in water delivery and treatment systems. Meeting the resource challenges of the 21 st century will require a more integrated approach to managing these resources. The first step to greater integration is to improve our understanding of how these resources are linked and the degree to which each depends on the other. Statewide Water-Energy Information Regional Water-Energy Information State Water Project Water-Energy Information Make all these maps have the same background. Understanding the relationship of water and energy is important for water management decision making on how to efficiently use limited water and energy supplies to meet increasing future demands. When making water management choices, the energy intensity of individual supplies can become part of the decision making process. Steps can also be taken by local water managers to reduce energy intensity related to raw water extraction and conveyance in their water management portfolios. Energy is used throughout the water sector to extract, convey, treat, distribute, and heat water and at the same time, water is used in the energy sector for extraction of natural gas and other fuels, used as the working fluid for hydropower, as the working fluid and for cooling water in thermal generation systems, and used to irrigate biofuels. This relationship is often called the water-energy nexus.

A large amount of statewide energy use is related to water. The pie chart below shows the types of energy that are used in California and includes how the energy is being used in the water sector. This graphic highlights the importance of water use habits of residential, commercial, and industrial users. Overall, about 12% of California’s energy use is related to water—most of which is related to end uses of water like showers and industrial processes. (CEC, 2013; CEC, 2005; CPUC, 2010 and 2011)CEC, 2013CEC, 2005CPUC, 2010 and 2011 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 half that energy comes from crude oil in the form of gasoline and diesel. About a third comes from electricity (including natural gas fired power plants and renewable electricity) and the remaining 19 percent comes from direct combustion of natural gas. A very small amount of crude oil based energy is related to water, but 32% of direct natural gas combustion and 19% of electricity use are related to water– together this represents about 12% of California’s total energy use. California has over 250 hydroelectric generating plants. Hydroelectricity provides California with about 10% 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 California Water Today.Volume 1 of the California Water Plan Update California Water Today. Water-Energy Nexus: Statewide

Energy Intensity is a measure of the amount of energy required per unit of production. For water, energy intensity gives us a measures of the amount of energy required to take a unit of water from its natural state and location (like a river or aquifer) and extract, convey, treat and deliver it to a user. Within California the energy intensity of water varies greatly depending on geography and water source. The map below shows California’s 10 hydrologic regions. Click on any region to see a summary of the Energy-Intensity of water supplies available in the region. Click on Region for More Information Regional Energy Intensity of Water Supplies Back-up documentation for all regional energy intensity data is available here. Energy intensity information is designed to help inform the public and water utility managers about the relative energy requirements of major water supplies used to meet demand. Because energy usage is closely related to GHG emissions, this information can support measures to reduce Greenhouse gases (GHG), as mandated by the State. Energy intensities of regional water supplies calculated here include only embedded energy from extraction and conveyance of water. Additional energy would be required to treat and deliver the water to end users. Treatment and delivery energy varies considerably based on treatment technology used and incoming water quality, delivery distance and geography. Treatment alone can add between 50 and 650 kilowatt-hours per acre-foot (kWh/AF) of water.

South Coast Hydrologic Region For additional information about the South Coast Hydrologic Region click hereclick here Energy Intensity (EI) in this figure is the estimated energy required for the extraction and conveyance of one acre-foot of water. The figure reflects only the amount of energy needed to move water from a supply source to a centralized delivery location (not all the way to the point of use). Small light bulbs are for EI greater than zero, and less than 250 kilowatt hours per acre foot (kWh/AF). Large light bulbs represent kWh/AF of water (e.g., four light bulbs indicate that the water source has EI between 1,501-2,000 kWh/AF). *The percent of regional water supply may not add up to 100% because not all water types are shown in this figure. EI values of Desalinated and Recycled Water have not been included in this diagram because the EI of these water supplies depends more on very localized factors rather than regional factors. Additional information about the EI’s of desalinated and recycled water see California Water Plan Update 2013 Volume 3, Resource Management Strategies 10 and 12. (For detailed descriptions of the methodology used to calculate EI in this figure click here)California Water Plan Update 2013 Volume 3, Resource Management Strategies 10 and 12. click here

Water-Energy Nexus: State Water Project The California State Water Project, owned and operated by DWR, delivers water to about 25 million Californians and 750,000 acres of irrigated farmland. Getting water to these users requires a large amount of electricity. In fact, the State Water Project is one of the largest single consumers of electricity in the state, using around 8,000 gigawatt-hours per year. The State Water Project also generates a large amount of electricity each year at its reservoirs and in conduit generating stations. The State Water Project actually generates about half of all the energy it uses each year. Even with all of the electricity the State Water Project uses it only accounts for about 0.3% of statewide total energy use and only about 3% of energy use related to water in the state. Energy generation and use along the State Water Project. The State Water Project starts in Oroville, California 70 miles north of Sacramento where water generates electricity as it is released from Oroville Dam. The water then flows down the Feather River and then Sacramento River by gravity (where some of it is used along the way by farms and cities. The water is then pumped out of the Sacramento/San Joaquin Delta where some of it is used in the San Francisco Bay Area. The rest flows down the California Aqueduct to farms and cities in the San Joaquin Valley, central coast, and southern California. Along the way it must be pumped by several pumping stations. Wherever the water flows down steep mountain sides, DWR has in conduit generating stations to recapture as much energy as possible. Detailed data on State Water Project energy intensity can be found here. How much energy does it take to deliver State Water Project water to my location? Click on a location along the aqueduct to find out the energy intensity of water at that location State Water Project Energy Intensity Calculator In the hydrologic region At SWP reach the energy intensity of SWP water is: kwh/AF The associated GHG emissions for this water are lbs. CO 2 e/AF Note: the State Water Project delivers raw water, meaning before this water can be used it must be treated which may add between 50 and 650 kWh/AF. It must also be delivered to a point of use which will require additional energy. These energy intensity calculations do not include any allowance for electricity generated at the Oroville Reservoir complex. Create new map zoomed into SWP area, include county boundaries, major cities and maybe Highways. DWR operates the State Water Project’s facilities to provide maximum benefit to the California electricity grid. DWR generates more electricity when statewide energy demands peak on hot summer days—reducing the need for inefficient and expensive power plants. DWR operates it energy consuming facilities more during evenings and nights when energy demand is low—this helps stabilize demand allowing other power plants to operate more efficiently. State Water Project electricity usage and Greenhouse Gases. DWR is committed to reducing the greenhouse gas (GHG) emissions associated with State Water Project electricity usage and adopted a GHG Emissions Reduction Plan in The plan calls for DWR to reduce emissions: GHG Emissions Reduction Plan 50% below 1990 levels by 2020 and 80% below 1990 levels by As of 2013, DWR has already reduced its emissions 30% below 1990 levels.