Modeling of Long-Duration Storage for Decarbonization of California Energy System

The project will develop improved modeling tools capable of analyzing future grid scenarios involving emerging storage and generation technologies.

The Regents of the University of California, Merced


Merced, CA

Recipient Location


Senate District


Assembly District



Amount Spent



Project Status

Project Update

The project team presented the results of their final analysis at a workshop in fall of 2023. The final results provide a high level assessment on the selection of long-duration energy storage (LDES) based on cost, duration, and efficiency. Feedback from CEC staff, the Technical Advisory Committee, and a previous workshops were used to develop the final grid scenarios. Results show that LDES with 8 hours of duration will be useful in extending the benefit of large solar and wind generation to provide 24-hour generation and LDES with 100 hours of duration or more may become increasingly useful in addressing seasonal energy imbalances as the year 2045 approaches. The role of LDES was assessed in scenarios involving different pathways for transportation electrification and alternative zero carbon energy technologies, and results are highly dependent on the costs and efficiencies assumed for the LDES.
More information including workshop materials may be found at…

The Issue

To meet California's clean-energy goals, low-cost solar and wind generation are a partial solution, but low-cost electricity is also needed when solar and wind generation are not available. While many new technologies show promise to provide the needed energy storage and demand management, their paths to market are uncertain. Modeling of California's energy systems requires extensive analysis of data including weather, geography, and the mixture of energy resources across the grid. The project's challenge is to aid in identifying which actions to take and what the timing of those actions should be by studying the roles and cost targets of storage technologies.

Project Innovation

The project is modeling the expansion of the grid using the SWITCH model and an improved version of the RESOLVE model which incorporates variable timesteps to allow full-year modeling. Modeling different grid scenarios, developed with feedback from industry experts, will help to define the role and useful cost targets for long-duration storage technologies as they are scaled to gigawatt levels.

Project Goals

Provide information useful to California to meet its energy demands and decarbonization goals.
Identify duration, efficiency, and cost targets for LDES to inform industry goals.
Inform utilities, researchers, and policy makers about the potential scale of LDES in the electric system.

Project Benefits

The project team will develop scenarios to reach California's clean-energy targets by updating modeling tools and analyzing broad datasets. Emerging LDES technologies are expected to have a critical role in achieving a zero-carbon grid by 2045, and understanding the interaction of LDES with other energy resources is an integral component of the study.

Economic Development

Economic Development

The project is analyzing strategies for meeting future grid requirements involving emerging storage and generation technologies.

Environmental & Public Health

Environmental Sustainability

The pathway to SB100 goals identified by this project will accelerate the transition to a zero carbon energy grid, leading to a reduction in greenhouse gas emissions.

Greater Reliability


LDES will serve a vital role in providing energy reliability in a deeply decarbonized grid with high penetrations of intermittent and variable generation. Energy storage with durations of 8 hours or more are capable of serving loads during prolonged periods of decreased renewable generation.

Key Project Members

Pictures of PIs and students from four campuses

Sarah Kurtz

UC Merced
Project Member

Patricia Hidalgo-Gonzalez

UC San Diego
Project Member

Dan Kammen

UC Berkeley



The Regents of the University of California on behalf of the Berkeley campus


The Regents of the University of California, on behalf of the San Diego campus


Match Partners


The Regents of the University of California on behalf of the Berkeley campus


The Regents of the University of California, Merced


The Regents of the University of California, on behalf of the San Diego campus


Contact the Team