
Solar panels produce energy at DWR’s Pearblossom Pumping Plant in Pearblossom, Calif. DWR/2018
Producing and Consuming Power
The State Water Project (SWP), operated by DWR, is both a major producer and consumer of electricity.
As the largest single consumer of electricity in California, the SWP pump load ranges from 6,000,000 megawatt hours (MWh) to 9,500,000 MWh depending on the type of water year (dry, average, wet). The electricity is used to operate the SWP pumping plants, which are needed to deliver the water throughout the State.
The SWP has one of the cleanest power portfolios of all major utilities in California. DWR has been proactively responding to the evolving power market by reducing reliance on fossil fuel energy resources, assisting in maintaining grid reliability, and controlling energy costs for water customers.
Fifty percent of the SWP’s power is provided by its own emission-free hydroelectric generation. The SWP, which is committed to reducing its carbon footprint, has a power portfolio consisting of 65 percent carbon-free resources, increasing to 75 percent by 2030 and 100 percent by 2045. DWR is finding innovative ways, such as adding solar to the system, to make this happen.
Producer of Electricity
DWR also produces electricity, which ultimately helps meet SWP’s power demands. The energy produced—which is highly variable due to changes in annual hydrologic conditions—averages around 6 billion kilowatt-hours (kWh) a year.
As a producer of electricity, we are subject to regulation under the authority of the Federal Power Act. We have three hydropower licenses and two conduit exemptions under authority of the Federal Energy Regulatory Commission. To maintain these licenses, DWR must comply with the terms and conditions to protect, mitigate and enhance beneficial public uses of hydropower projects.
The SWP uses five hydroelectric generating plants and four hybrid pumping/generating plants to generate clean power. DWR sells the power it generates from the SWP to the California Independent System Operator (CAISO) market, during peak demand hours and help displace fossil generation and lower overall grid greenhouse gas (GHG) emissions. The revenue from these sales helps keep the net cost of water deliveries more affordable.
The SWP’s flexible pumping operations help it to manage the timing of its power needs. This flexibility is allowed by Project reservoirs, which temporarily store water until it is needed to meet the daily and seasonal demands of its contracting agencies.
To reduce power costs, pumping is minimized during on-peak hours when power prices are highest. Maximum pumping is scheduled during off-peak periods (nights, solar hours, weekends and holidays) when power costs are cheaper. Thus, the SWP can purchase, when needed, inexpensive surplus generation from other power suppliers for its pumping operations.
Buying Power
The Department has also been in the business of purchasing power. In response to the turn-of-the-millennium energy crisis, Governor Gray Davis signed an Executive Order in January 2001 that ordered DWR to purchase energy for California’s three investor-owned utilities.
At that time, Pacific Gas & Electric, Southern California Edison, and San Diego Gas & Electric were on the verge of bankruptcy and unable to make purchases. DWR established the California Energy Resources Scheduling division (CERS) to buy and sell electricity on behalf of big utilities and to purchase the remaining energy requirements (“net short”) for their retail customers.
CERS actions helped stabilize the wholesale power markets in California and returned electricity prices to reasonable levels. CERS has been transitioning operating responsibility back to the utilities and has a planned sunset of 2022.
In support of a broader effort to safeguard our state’s energy grid in the face of climate-induced drought, wildfires, and extreme heat waves, the California Department of Water Resources (DWR) has procured temporary power generators throughout California.
Because of DWR’s expertise as a water and power utility, Governor Newsom’s emergency proclamation issued on July 30, 2021 directed DWR to work with the California Energy Commission (CEC) to develop projects to expand power generation and energy storage facilities to respond to energy shortages due to extreme events, such as heat waves or wildfires.
DWR began the process of procuring temporary power generators in Summer 2021 for use during extreme events. With new legislation enacted in June 2022, DWR procured additional generators which will be operational by fall of 2023 in support of such actions.
Of the Generators already procured and installed, two units are located at sites in Roseville and Yuba City. The additional units will be positioned in the San Joaquin Valley region.
The units will be placed at existing facilities where they can feed directly into the electric grid and be dispatched as needed by the California Independent System Operator (CAISO) and Western Area Power Authority (WAPA).
The units are 390 KW in size and powered by natural gas. The units will be available for use during extreme events for a minimum of five years at which time they may be extended if the need is still present or redeployed to other locations.
DWR is taking on this effort in collaboration with the California Energy Commission (CEC), the California Public Utilities Commission (CPUC) and the California Independent System Operator (CAISO).