Multi-Customer Solar Microgrid Supports Calif. Airport, Coast Guard Operations

California Redwood Coast-Humboldt County Airport and U.S. Coast Guard Air Station’s 100% renewable energy, front-of-the-meter, multi-customer microgrid is fully operational in California. The new microgrid was developed through a partnership between the County of Humboldt, Pacific Gas and Electric Co. (PG&E), Schatz Energy Research Center at Cal Poly Humboldt, Schweitzer Engineering Labs, Redwood Coast Energy Authority, Tesla Inc., The Energy Authority, and TRC.

Redwood Coast Airport Microgrid, (RCAM), features a 2.2MW solar photovoltaic array. This array is DC-coupled and connected to a 2MW (9.MWh) battery storage system. The system is made up of three Tesla Megapacks. It also includes a microgrid control system, with protection and isolation devices that interfaces directly with PG&E’s distribution control center.

The microgrid has multiple functions and is managed by project partners. The Schatz Energy Research Center serves as the prime contractor and technology integrator for the design, development, testing, and deployment the clean energy microgrid.

“The Redwood Coast Airport Microgrid has ushered in a new and exciting era for the electric grid in California,” says Peter Lehman, founding director of the Schatz Center and project lead. “With its successful deployment and the development of new microgrid agreements and tariffs, RCAM has become a role model and beacon to communities across the state who are striving to green their energy supply and bolster their resilience in the face of climate change.”

Redwood Coast Energy Authority, the Community Choice Aggregator for Humboldt Bay, owns the two solar arrays as well as the battery storage system.

RCAM generates renewable energy for the North Coast in standard blue-sky operation. RCAM participates the California Independent System Operators (CAISO), wholesale markets for energy, including the real-time and ancillary service markets.

RCAM is a way to store solar energy during the daylight and release it on the grid at night when it is most needed. It also supports grid reliability and creates an economic basis for future microgrids.

“RCEA’s goal is to provide our customers with 100 percent carbon-free electricity by 2025, and 100 percent local carbon-free electricity by 2030. This project is a major milestone for our clean energy and resilience efforts,” states Matthew Marshall, executive director of RCEA, which works closely with schools, fire departments, tribes and other local agencies to support community resilience across the North Coast.

PG&E owns, operates and maintains the microgrid circuit and controls the microgrid during “islanded” operation. In the event of a broader grid outage, the clean-energy microgrid provides indefinite power for the 19 connected customers by disconnecting or “islanding” from the broader grid when needed and becoming an independent, PG&E-operated grid segment. This ensures that rescue operations as well as airport flight service can continue uninterrupted.

“The Redwood Coast Airport Microgrid represents the culmination of many years of research, innovation and collaboration by the world’s leading microgrid experts,” comments Jason Glickman, PG&E’s executive vice president of engineering, planning and strategy. “Thanks to this team’s smart work, microgrids now play a key role in PG&E’s ongoing efforts to harden our electrical system and enhance local grid resilience throughout Northern and Central California. We know how much our customers and communities need reliable energy, and this system not only increases local reliability, it also serves as the foundation for a replicable and scalable model for widely deploying multi-customer microgrids across PG&E’s service area. This gives communities a new tool in securing their resilience and clean energy goals.”

The California Redwood Coast-Humboldt County Airport is located in McKinleyville (Calif.). It serves the greater North Coast community and handles over 50,000 flights annually, including private, commercial, and emergency medical flights. The U.S. Coast Guard Station Humboldt Bay is located adjacent to the airport and provides search-and-rescue for 250 miles along the coast, from the Mendocino County border to the California-Oregon boundary.

Roads into Humboldt County often close due to fires and mudslides. Air services are crucial in emergency response.

“The California Redwood Coast-Humboldt County Airport (ACV) is a lifeline to our community every day by keeping Humboldt County connected to the world alongside our partners at United Airlines, Avelo Airlines, American Airlines, REACH/Cal-Ore Life Flights, U.S. Coast Guard-Sector Humboldt Bay and many others,” says Cody Roggatz, Humboldt County’s director of aviation. “RCAM ensures that we can continue to keep that lifeline open through energy resilience, no matter what happens to the power grid.”

Research and development for the microgrid was supported through California’s Electric Program Investment Charge (EPIC) – a statewide, customer-funded program that enables PG&E, other California investor-owned utilities and the California Energy Commission to execute emerging technology demonstration and deployment projects that address important grid needs. EPIC plays a role in helping drive the innovation needed to meet California’s policy and clean energy goals while also ensuring the safe, reliable and affordable operation of the grid.

The collaboration between RCAM project partners has informed technical and policy innovations including the development of the Community Microgrid Enablement Tariff and PG&E’s Community Microgrid Enablement Program (CMEP).

To date, PG&E has engaged with more than three dozen communities and customers to explore potential financial and infrastructure support options for developing microgrids and resilience solutions through the CMEP.

Additionally, PG&E, along with Southern California Edison and San Diego Gas and Electric, are developing the Microgrid Incentive Program (MIP), leveraging a $200 million statewide fund dedicated to the development of clean energy microgrids supporting the critical needs of vulnerable populations and disadvantaged communities. This program is expected to be launched in late 2022 by the companies.

Together, the MIP and PG&E’s CMEP provide comprehensive financial support for both the distributed energy resources and other costs necessary to develop and energize a microgrid, as well as the distribution upgrades necessary to enable the safe islanding of the microgrid.

The Schatz Center has partnered with several tribes in Northern California for climate support, resilience, and clean energy. Cal Poly Humboldt recently started designing a renewable energy microgrid in order to increase campus resilience and clean generation. This microgrid will be part of the university’s sustainability framework, and will enable students in engineering, environmental sciences and other programs to gain hands-on experience with innovative climate-friendly technologies.