Opinion: San Vicente hydroelectric project a smart way to make power grid more resilient

It will provide electricity at night after solar power goes slack

By The San Diego Union-Tribune Editorial Board

July 29, 2021 4:56 PM PT

The editorial board operates independently from the U-T newsroom but holds itself to similar ethical standards. We base our editorials and endorsements on reporting, interviews and rigorous debate, and strive for accuracy, fairness and civility in our section. Disagree? Let us know.

The state government’s decision to provide $18 million to fund preliminary work on state and federal approvals for the long-anticipated San Vicente Energy Storage Facility — advocated by the San Diego County Water Authority and the city of San Diego — makes the $1.5 billion project significantly more likely to come to pass. The great news is that the “pumped hydro” facility at the San Vicente Reservoir near Lakeside will strongly shore up available energy supplies at night after solar power is no longer directly available.

The project will require the building of another, much smaller reservoir at a higher elevation than San Vicente. During the day, when energy supplies are plentiful, water will be pumped to the higher reservoir. At night, when needed, that water can be released into the lower reservoir, generating hydroelectric power. The project will generate enough electricity for 135,000 households and make it easier for the region to keep the lights on as it pursues a statewide goal of ending all use of energy sources that generate greenhouse gases by 2045.

The $1.5 billion price tag may seem daunting. But the Water Authority says the $18 million in state funds is the only money that will be taken from taxpayers. The authority and the city will begin looking for a private developer to partner with on the project next month. That developer will fund the project and then recoup its investment on the back end after the facility begins generating power. Based on what’s known, this seems like a welcome example of thoughtful government in action.

First steps taken to make pumped hydro energy storage project at San Vicente Reservoir a reality

$18 million from state budget earmarked for joint effort between the city and SD County Water Authority

By Rob Nikolewski

July 26, 2021 3:03 PM PT

With an $18 million boost from the state, a major energy storage project using hydroelectric power is taking shape at the San Vicente Reservoir, nestled in the Cuyamaca Mountains near Lakeside.

The long talked about San Vicente Energy Storage Facility — proposed by the city of San Diego and the San Diego County Water Authority — received the funding earlier this month when Gov. Gavin Newsom signed the state budget. The $18 million will be spent to tackle some of the preliminary work needed to make the “pumped hydro” project a reality, such as initial design, environmental reviews and federal licensing.

“We believe the project is a critical component to meeting the state’s needs for integrating renewables” into the power grid, said Gary Bousquet, deputy director of engineering at the County Water Authority.

Next month, the city and the Water Authority expect to issue requests for proposals and eventually line up a private partner to take on what’s estimated to be a $1.5 billion construction and development project.

Pumped hydro projects have been part of the nation’s energy grid for more than 100 years. The concept is pretty basic: Using turbines, water is pumped from one reservoir up to another at a higher elevation. The water is then released and the ensuing rush of water generates electricity.

Using pumped hydro projects as a means of storing energy has taken on a greater focus as California moves forward on its goal to derive 100 percent of its electricity by 2045 — if not sooner — from sources of power that do not release greenhouse gases into the atmosphere.

California’s grid has integrated more renewable energy sources, but solar and wind are intermittent — that is, solar power is produced only when the sun shines and wind power flags when the breezes don’t blow. Other sources are needed to fill in the gaps. Natural gas can do the job, but it is a fossil fuel.

Energy storage, such as batteries, has increasingly become a potential solution. But so has pumped hydroelectric storage, and that’s what the city and county are looking for the San Vicente Energy Storage Facility to do — providing an estimated 500 megawatts of electricity when the grid needs it.

For perspective, when the San Onofre Nuclear Generating Station was up and running, it accounted for a little over 2,000 megawatts of power.

In addition, while the duration of battery storage usually is four hours, the San Vicente Energy Storage Facility would provide electricity for a longer duration — for eight hours and 4,000 megawatt-hours per day. The project is expected to provide enough energy for about 135,000 households.

The already existing San Vicente Reservoir that holds up to 247,000 acre-feet of water would act as the lower reservoir, and an upper reservoir estimated to hold about 8,000 acre-feet of water would be built at a higher elevation into the hillside. A tunnel system and an underground powerhouse containing four reversible pump turbines would connect the two reservoirs.

When there’s plenty of solar and wind getting generated during the day, “you can pump water up the hill,” Bousquet said. “And then at the end of the day when everybody comes home from work and air conditioning is turned on and the solar is coming offline, you could energize this facility, flow water downhill and meet the needs (of the grid) during that time.”

Electricity from the project can be fed into a nearby San Diego Gas & Electric substation.

David Victor, a UC San Diego professor who co-directs the university’s Deep Decarbonization Initiative, has been a strategic consultant to the city of San Diego on the San Vicente Energy Storage Facility. Victor says pumped hydro projects should be seen as a “quiver of arrows the state needs to have when you put a lot of renewables” on the grid.

“This is to some degree uncharted territory,” Victor said. “There’s no large grid that ever made such a transformation so quickly as what’s going on in California … There’s a lot of that that still need to be worked out with regard to the grid of the the future for California, but one of the things that all the models point to is that there’s this big increase in the need for storage of different types.”

The San Vicente project will be a closed-loop system that will hold water that is not reliant on runoff so it should be insulated from year-to-year fluctuations that can hamper hydropower production. The Water Authority said the project will not interfere with existing water supplies, water quality, fisheries or recreational activities at San Vicente.

“Over the last 20 years, the Water Authority and the city have built the emergency storage project, which raised San Vicente Dam, and behind the dam we keep a supply of water for emergencies,” Bousquet said.

After the request for proposals go out in the coming weeks, Bousquet said potential partners will be interviewed. Eventually, the San Diego City Council and the Water Authority Board will approve the entity selected to proceed with the environmental and licensing work. The project is scheduled to be completed in 2030.

“Once we have the project development agreement, the developer puts up all the money to advance the project,” Bousquet said. “They get financing and they put all that money upfront and then they collect their money on the backend once the facility is in operation. So one of the key benefits is that no taxpayer dollars are needed to develop the project” beyond the $18 million coming from the state budget.

The $18 million figure includes California Environmental Quality Act and federal government’s National Environmental Policy Act reviews, as well as licensing from the Federal Energy Regulatory Commission.

There’s already a pumped hydro storage facility in San Diego. Lake Hodges has a two-turbine pumphouse that sends water up 770 feet from the city-owned Hodges Reservoir to the the Water Authority’s Olivenhain Reservoir more than a mile away, generating some 40 megawatts of power on demand. At 500 megawatts, the proposed San Vicente project would generate more than 12 times the electricity of the Lake Hodges facility when at full capacity.

According to the California Energy Commission, four pumped storage facilities are used to help California’s grid during times of peak energy demand: Castaic Lake in Los Angeles County, with 1,331 megawatts of nameplate capacity (generation under ideal conditions); Helms in Fresno County, with 1,212 megawatts; Eastwood in Fresno County at 200 megawatts; and Lake Hodges.

San Vicente Energy Project allocated $18 million in state budget

REGION — The San Vicente Energy Storage Facility received $18 million from the state budget signed this week by Gov. Gavin Newsom, the San Diego County Water Authority announced on Friday.

The money is enough to advance the large-scale renewable energy project through the initial design, environmental reviews and the federal licensing process.

The project is an effort by the city of San Diego and the water authority.

According to the Water Authority, the San Vicente project “is one of the most promising pumped energy storage solutions in California and it would be a major asset to help avoid rolling blackouts through on-demand energy production while helping to meet state climate goals.”

Proponents say the project could mitigate water ratepayer costs across the San Diego region by generating additional revenue to help offset the cost of water purchases, storage and treatment.

When completed, the San Vicente energy project would provide up to 500 megawatts of long-duration stored energy to meet peak electrical demand periods throughout Southern California.

The energy project would create a small upper reservoir above the existing San Vicente Reservoir in Lakeside, along with a tunnel system and an underground powerhouse to connect the two reservoirs.

Its powerhouse would contain four reversible pump turbines, which would pump water to the upper reservoir, where it would act as a battery of stored potential energy.

It would also help meet the goals of Senate Bill 100, which requires 60% renewable energy by 2030 and 100% zero-carbon energy resources statewide by 2045.

According to the water authority, the project would provide enough energy for about 135,000 households once fully operational.

Water authority board Chairman Gary Croucher credited state leaders and agency staff members who have collaborated on the project for years.

Croucher also thanked Newsom and Senate President Pro Tem Toni G. Atkins, D-San Diego, “for ensuring funding for this critical infrastructure project, which will create more than 1,000 construction-related jobs in addition to its other benefits.

The city and the water authority teamed seven years ago to raise the height of the city-owned San Vicente Dam by 117 feet.