California High-Speed Rail Authority Advances Solar-Storage Project Permitting Amid Funding Review

The California High-Speed Rail Authority (CHSRA) has initiated the permitting process for a 265MWh hybrid solar and battery energy storage system (BESS), designed to serve as the primary power source and backup for part of the first phase of California’s High-Speed Rail project, which runs between Merced and Bakersfield. This step comes amid significant challenges for the rail project, which has recently faced increased scrutiny due to extensive delays and rising costs.

On February 18, 2025, the CHSRA published a notice of preparation (NOP) as part of the California Environmental Quality Act (CEQA) review process, signaling its intention to conduct a comprehensive environmental review of the Central Valley Solar and BESS project. The NOP not only kicks off the CEQA review but also invites feedback from the public and stakeholders regarding the scope of the forthcoming environmental impact report (EIR). Comments on the EIR’s scope can be submitted until April 8, 2025. Notably, RAI Energy is at a similar stage in the permitting process for a large 3.2GWh solar and BESS project in Imperial County, California.

The Central Valley solar and BESS project will be deployed across four sites owned by the CHSRA along the Merced-Bakersfield route at various traction power substations (TPSs), connecting to the California Independent System Operator (CAISO) network to meet the energy demands of the rail system. Below are the details of the four battery storage systems expected to connect to the grid via Pacific Gas & Electric (PG&E) transmission lines:

CHSRA plans to use lithium iron phosphate (LFP) battery technology for the Central Valley project, which is commonly adopted in utility-scale battery projects worldwide. Although the BESS units are expected to have a lifespan of over 25 years, the authority intends to replace them every 15 years. Construction of the Central Valley project is anticipated to begin next year and reach completion by 2028.

According to a sustainability report released by the CHSRA in 2024, the entire rail project, stretching 494 miles between San Francisco and Los Angeles, will be powered by renewable energy sources, chiefly solar and BESS. Future plans include extending the project north to Sacramento and south to San Diego. The report indicates that the project will generate sufficient solar and BESS capacity to power the entire rail line, with enough surplus energy to cover approximately six hours of blackout. To address the inherent variability of solar power, the CHSRA intends to purchase electricity from CAISO when it is “readily available and inexpensive.” By utilizing stored energy from the solar farm during peak operating hours, the CHSRA anticipates reducing its energy costs by 50-75%. The sustainability report also mentions the potential for the CHSRA to receive payments from CAISO for grid services in various markets.

Despite the progress, the CHSRA is currently undergoing a compliance review initiated by the US Department of Transportation’s Federal Railroad Administration, which may affect federal funding. In a letter dated February 20, 2025, CHSRA CEO Ian Choudri was informed of the impending review and the risk of losing federal support. During the prior Trump Administration, federal funding of $929 million for the project was terminated in 2019, but it was reinstated in 2021 under the Biden Administration, which subsequently allocated an additional $3.073 billion in funding in 2023.

In 2008, California voters approved over $9 billion in state bonds to finance the high-speed rail project, initially expected to be completed by 2020. However, due to considerable delays, the first 171-mile segment connecting Merced and Bakersfield is not projected to be finished until 2031, as noted in a recent report from the US Office of Inspector General. The CHSRA’s latest business plan estimates the total cost of the high-speed rail project to be between $88.55 billion and $127.93 billion, significantly exceeding initial estimates of around $33 billion. From July 2006 to June 2024, the CHSRA has invested over $13 billion in the project, which it claims has generated $21.8 billion in economic activity and created approximately 109,000 job-years of employment.