To help fulfill its commitment to providing 100% renewable energy for the operation of the high-speed rail system, the California High-Speed Rail Authority (the Authority) intends to build a series of photovoltaic (PV) solar systems and battery energy storage system (BESS) facilities in the Central Valley.
In 2008, the Authority conducted a study indicating that the high-speed rail system would be powered by the California grid. In 2012 and 2014, the Authority approved the construction of the Merced–Fresno and Fresno–Bakersfield segments, respectively, as part of the statewide system.
To supply power to the system, it has been approved to build traction power substations (TPSS) at intervals of approximately 30 miles along the route. The TPSS is responsible for converting electricity from multiple sources to ensure the availability and quality of traction power supplied to the overhead contact system (OCS). The OCS delivers electricity directly to trains via overhead lines, enabling them to operate on the rail network. To reduce reliance on third-party infrastructure improvements, optimize the project’s operational cost structure, and align with the goal of using 100% renewable energy to power the system, the Authority intends to integrate PV solar fields and BESS installations as part of the overall system.
PV sites will generate electricity, which will be transmitted to the TPSS and stored in co-located BESS units. The BESS units will dispatch electricity during peak demand periods to optimize costs and provide backup power, ensuring continuous operation for up to six hours during power service interruptions. While the PV sites will serve as the primary power source, each TPSS will remain connected to the grid to supplement energy during periods of limited solar production, ensuring uninterrupted service. This configuration enhances the reliability of traction power while enabling the Authority to (1) advance its sustainability commitments, (2) achieve greater energy resilience, and (3) minimize reliance on third-party-driven grid infrastructure upgrades.
