Microgrid technology has emerged as a promising solution to address the challenges posed by Public Safety Power Shutoffs (PSPS) in California. In the past, Pacific Gas and Electric (PG&E) has led the development of temporary distribution microgrids for PSPS mitigation through the use of diesel-backed generation. This pioneering pilot in Calistoga, California, focuses on replacing existing temporary diesel generation with a permanent, clean energy solution that will enable Calistoga to have clean, long-duration power during future PSPS events.  

The pilot consists of a hybrid system which includes Hydrogen Fuel Cells combined with a Battery Energy Storage System (BESS); it will deliver a peak power of 8.5 MVA and generate at least 293 MWh of energy to meet the city’s energy demands during a PSPS event.

his is PG&E’s largest and first of its kind microgrid project utilizing third party owned Hydrogen Fuel Cell generation. The project has involved complex protection and microgrid control system design to enable the use of multiple boundary points, blackstart operation, and inverter-based resources. A notable aspect of this pilot project is PG&E’s first implementation of a standardized Microgrid Islanding Study (MIS).

This presentation will share the accomplishments and challenges PG&E has experienced through the design and development of this microgrid, including communications system considerations, MIS scenarios, and operational logistics across the multiple stakeholders involved in its development and operation.