- The San Diego County Water Authority and the City of San Diego are testing the waters on a pumped storage project that could help provide the region with up to 500 MW of clean energy, Windpower Engineering reports.
- The agency last week released a joint request for letters from electric utilities, developers, investors and energy consumers, to try and gauge interest in the project.
- Central to the proposal is an interconnection and pumping system between the existing San Vicente Reservoir and a new, smaller reservoir located uphill.
The pumped storage project being considered by San Diego could power more than 300,000 homes, while also helping add renewable energy to the grid in times of high demand. The project would also enhance the city's efforts to run on 100% renewable energy by 2035. The Water Authority and the City of San Diego have a preliminary permit from the Federal Energy Regulatory Commission, allowing the agencies to pursue the development near the San Vicente Reservoir.
“When we filled San Vicente Reservoir last summer, we filled it with more than just water – we filled it with huge potential for energy benefits,” Mark Muir, chair of the Water Authority Board of Directors, said in a statement last week. “Given this new potential for energy from a recently expanded water resource, it’s only prudent to continue to research the potential benefits to our region’s ratepayers.”
The project calls for creating a small reservoir above the existing San Vicente Reservoir, and a tunnel system and underground powerhouse to connect the two reservoirs. According to the city, the powerhouse would contain four 125 MW reversible pump-turbines to move water to the upper reservoir or generating power as it flows down during peak demand. In off-peak hours, water will be pumped into the upper reservoir, the city said in a description.
Letters of interest are due Feb. 15. An estimated value on the project is not available yet, but further details on the solicitation can be found on the Water Authority's contracting opportunities page here.