With Energy Security in Mind, Miramar Breaks Ground on Microgrid
By GIDGET FUENTES, Special Correspondent
SAN DIEGO — Officials at the Marine Corps’ busiest airfield on the West Coast broke ground Sept. 28 on what will be critical node to ensure energy security when the next blackout strikes.
The $19.29 million microgrid project at Miramar Marine Corps Air Station (MCAS) is slated to be completed late next year and be operational by early 2019. The project, led the Marine Corps and Naval Facilities Engineering Command-Southwest, will integrate several power generators combining fossil fuels and renewable energy sources into a single, small power grid.
The facility will include advanced control systems and an operations center, along with power generated by a 16-megawatt solar photovoltaic array, a 6.45-megawatt diesel and natural gas power plant and 3.2 megawatts generated from methane produced by decaying debris at the adjacent city landfill. The solar, or PV, system includes existing panels on carports and rooftops. Electronic controls will help manage and balance the sources of power into the microgrid, officials said.
“We will be able ... to self-sustain,” Col. Jason Woodworth, the air station commander, told the ground-breaking crowd, adding that capability that will be important in an emergency, as the air station could better support an emergency operations center or emergency response at the airfield.
“When the demand on the grid is high, we will be able to reduce our demand from the base by starting the power plant ... and reduce the demand on the grid out in town, thereby helping to stabilize the grid out in town,” Woodworth said, adding that energy resiliency “is pretty self-explanatory.”
If the regional electric grid suffers an outage, like the nine-hour blackout Miramar experienced in 2011, the installation-level microgrid would ensure that more than 100 facilities, including the flight line and support, would have uninterrupted power to continue operations.
“This is a really complex, innovative thing we are doing here, taking large amounts of renewable energy and combining it with a central, conventional power plant to provide backup power to the installation,” Mick Wasco, Miramar’s energy program manager, told the crowd at the afternoon event. He’s been involved in the idea since 2012.
“This is not just backup power. ... This is a redundant source of power that will provide us 100 percent of capability in over 100 mission-critical buildings on the base and within the entire flight line,” Wasco said.
A demonstration in June 2016 showed the benefits of a building-level microgrid that would operate on its own — known as “islanding” — using local, renewable solar energy combined with storage capability without relying on the wider power grid.
Miramar will retain its link to the local grid, with San Diego Gas & Electric (SDG&E) continuing to provide its electric and gas needs.
“We’re still connected to the grid,” Wasco said told Seapower. “When we take less from SDG&E, there’s more available for SDG&E to give somewhere else.”
Andy Haun, chief technology officer with Schneider Electric, hailed the “ecostructure” that helps manage connected loads merged in a control system that “allows you to interoperate with the grid and be smart about the right choices you use energy from the grid and/or not from the grid.”
Schneider Electric, an Andover, Mass.-firm, is a joint partner in Miramar’s microgrid with Black & Veatch, based in Overland Park, Kan.
“It actually brings resiliency on site, resiliency for the operations here,” said Haun. “It allows us to manage the resilient resources that are locally generated to secure the environment through load management and load control systems.”
The Sept. 8, 2011, regional blackout that impacted Miramar illustrates the importance of resiliency and redundancy.
The blackout began when an Arizona Public Service technician’s error during a maintenance check at the North Gila substation near Yuma, Ariz., caused an 11-minute disturbance across the regional electric grid. It knocked out power to a critical, 500-kilovolt high-voltage transmission line feeding the grid servicing part of the Southwest, according to a 2012 Federal Energy Regulatory Commission and North American Electric Reliability Corporation report on the incident.
That mistake began about 3:30 p.m. on a typically hot September afternoon, and had a “ripple effect” across the power grid, according to a federal investigation. Some 2.7 million customers — about 5 million people by some estimates — were in the dark overnight across Southern California and parts of Arizona and Baja California, Mexico, as electric power ebbed across interconnected, local grids.
It also left the San Diego area, and Miramar MCAS and its busy flight line and operations supporting West Coast Marines, in the dark before full power was restored regionally 11 hours later.
“This stands to date still the largest power outage in California history,” Navy Lt. Cmdr. Travis Brinkman, Miramar’s power works officer and a Navy Seabee, told the crowd.
The federal investigation into the outage found that while the utility worker’s actions managing loads precipitated the outages, “weaknesses” by systems operators failed to secure the the interconnected distribution grid from the power fluctuations over an 11-minute period that led to the widespread blackout.
Miramar “went for over nine hours without power,” Brinkman said. It was eye-opening, “the fragile nature of our power grid and what we rely on, as well as the need for a large-scale, energy security system for Marine Corps Air Station Miramar.”
That experience, and lessons learned, prompted the project for the microgrid.
“We need something, in the event of an earthquake that may devastate the power grid. We need a way the installation can still operate for humanitarian relief and things along those lines,” Brinkman told Seapower after the ceremony. “It allows us to operate our core missions, regardless of what’s going on outside of our fence line.”
The microgrid won’t power the entire base, but it will be focused on mission-critical facilities, he added.
The microgrid will help ease demands in heavy-use days such as heatwaves or during outages, from power drawn from the local SDG&E.
“On a daily basis, this system will be operating to help reduce that load on the outside grid,” Brinkman said. Miramar officials are working on a power arrangement with SDG&E, since it is its primary power provider.
The landfill generation has been operating since 2012, providing a constant source of energy, even at night when PV systems go silent. Miramar already generates 55 percent of its electricity through renewable energy, a figure that will grow to 75 percent once the microgrid is operational, Woodworth said.