What is the proposed San Vicente Energy Storage Facility?
The proposed project would use existing resources to increase power grid reliability in San Diego County and help keep the lights on, especially during heat waves and other periods of high demand. The project is proposed to use the existing San Vicente Reservoir, construct a new upper basin along with an underground pump-turbine system to generate energy. The 500 MW system would produce enough clean energy to power the equivalent of 135,000 households.
Why is this project being proposed for San Vicente Reservoir?
San Vicente Reservoir offers a few important advantages that make it ideal for pumped storage. One of the main benefits is a large existing water body near hills that rise steeply from the lake. That creates the potential to use the significant change in elevation to create hydroelectric power. Another benefit is that the reservoir is just a few miles from a power substation, which allows for the energy to put on the power grid.
Who is proposing this project?
The San Diego County Water Authority and City of San Diego are considering this project as partners. The City owns and operates San Vicente Reservoir and owns lands surrounding the reservoir, while the Water Authority owns about two-thirds of the water in the reservoir. The public agency partners are planning to enter an agreement with a private developer in early 2023 to advance the feasibility phase of the project. The $1 billion Carlsbad Desalination Plant was built and operated under a similar public-private approach.
Who is doing the work?
The City of San Diego and the San Diego County Water Authority are jointly developing the project to take advantage of their shared assets at San Vicente Reservoir. They are negotiating with a private developer – BHE Kiewit – to develop, commercialize and operate the project.
How will this project be paid for?
Ultimately, the project will be paid for by energy users. It was designed to replace expensive out-of-state power that’s currently imported to meet peak demands. Energy users will be purchasing power one way or the other; the question is whether or not it’s locally controlled clean energy.
How will it work?
The proposed project would produce clean power by using renewable energy during the day to pump water from the San Vicente Reservoir to a smaller upper basin. When the sun goes down and household/business demand goes up, the pooled water would be released downhill through the pipeline to spin turbines and generate electricity. In this way, clean energy could be supplied during the evening when the sun goes down and solar power production declines.
Why is this project important?
The proposed San Vicente Energy Storage Facility would create several important benefits, such as:
- Helping stabilize the energy grid and enhancing system reliability
- Producing clean energy on demand, especially during high-use periods
- Storing surplus renewable wind and solar energy that would otherwise be lost
- Increasing energy independence.
- Generating additional revenue and help offset water rate increases
- Contributing to the state and local goals of a carbon-free future
Where will the project be located?
San Vicente Reservoir is near the community of Lakeside in eastern San Diego County. If the project moves ahead, a new upper basin will be developed adjacent to the existing reservoir at a site that has yet to be determined.
Can we use industrial batteries instead of pumped storage?
Long-term grid reliability is best approached with a portfolio of clean-energy strategies. While batteries play a role, they don’t have the same capacity as pumped storage to deliver energy over many hours. Pumped storage provides grid stability that is needed to keep the grid operational and safe. In addition, pumped storage projects can operate for 100 years or more –longer than batteries.
How long will it take to develop this project?
The project partners expect to go through the state and federal regulatory review processes through 2026, with construction potentially starting in 2027 and continuing for about five years.
Will this project create jobs?
The proposed pumped storage project would create tens of thousands of work-hours of pre-construction activities such as environmental assessment, permitting and project management. In addition, it would create hundreds of construction jobs during at least four years. In addition, there will be permanent jobs associated with the project. Job creation estimates will be refined as the project comes into focus.
Will the project impact existing uses of the reservoir, such as water storage and fishing?
San Vicente Reservoir offers a variety of recreation activities including boating, fishing, and picnic space. The project is expected to have very little impact on existing uses. It will not consume water, and changes in reservoir levels in San Vicente Reservoir would not exceed the current fluctuations during normal operation or beyond seasonal changes. It is not expected to hamper fishing or boating in the reservoir, except in a safety zone near the pump turbines.
How will the project connect to the power grid?
The proposed project is anticipated to connect to the power grid through a new transmission line to an existing substation approximately 6 miles from San Vicente Reservoir.
What type of work is currently being done?
In 2022 and 2023, the project partners are working with expert consultants to perform data collection and environmental studies near the potential project site. Surveys and studies include visits by specialists such as biologists, archaeologists, and engineers. Survey work is expected to include the use of drones to photograph project-related areas and support the various kinds of studies. In addition, helicopters will be used for less than two months to transport equipment to and from remote sites where limited geotechnical work will be done.
How much will the project cost and how is it being funded?
In 2021, the State of California invested $18 million in the project, funding initial design and environmental and feasibility studies required to prepare the project for state and federal regulatory and licensing review processes. The overall cost of the project and a financing plan will be determined after a private developer is brought onboard.
Are there similar projects like this elsewhere?
Hydropower has been used across the nation and around the world for centuries. Pumped storage projects are also widely used. For instance, the Water Authority operates a similar – but much smaller – pumped storage facility that generates energy by moving water between Olivenhain Reservoir and Lake Hodges in North County.
When will the project be done?
If constructed, the project is expected to be operational in the early 2030s. A decade of development is normal for major projects that require extensive environmental reviews, a federal license and complex construction.
Will the reservoir be closed for construction?
Construction plans have not been developed, however, the project is not expected to result in lengthy reservoir closures. Most of the work would be in the hills above San Vicente Reservoir, minimizing impacts to reservoir users.