Military microgrid promises community power for 14 days during disasters

In Oregon, earthquakes and fires are the biggest disaster worry, and the Oregon Military Department (OMD) wants to be ready with a newly deployed military microgrid in the city of Dallas that can provide power to the Colonel Nesmith Readiness Center and community members for up to 14 days during outages.

After 33 months of preparation, a microgrid at the 40,000-square-foot readiness center, an Oregon National Guard Armory, was deployed in early September.

The readiness center will be powered during outages by a microgrid that includes 225kW of solar, a 128kWh Blue Planet Energy battery, an Ageto Energy controller and an existing 150kW diesel generator.

It’s expected to serve as a community resource during disasters, such as earthquakes, fires and storms, that spark outages, said Justine Sanchez, solar plus storage director for Mayfield Renewables, which provided feasibility studies, design and engineering for the project.

During disasters, the facility could act as a command center or as a Red Cross shelter for example. Its exact use will be determined by the OMD based on the need.

Backed up by the microgrid will be existing emergency and standby systems. The backed-up circuits include heat and air conditioning, communications and lighting, said Ryan Mayfield, founder and CEO of Mayfield Renewables.

The facility, a community center for Polk County, is a training center for the 162nd Combat Engineering Company of the Oregon National Guard. It includes a large assembly hall, administrative spaces, a commercial kitchen, military storage, an arms vault, a weapons training simulator and an outbuilding for vehicle maintenance.

Second military microgrid coming next year

The OMD, which oversees the state of Oregon’s armed forces, is also planning a separate microgrid project, due to be deployed in first quarter 2022, in a different location — the Anderson Readiness Center in Salem, the state’s capitol.

Portland General Electric, which serves the Anderson Readiness Center, will install, own and operate a 500kW/1MWh battery that will be part of the microgrid.

The military department recently completed installing 268kW of solar PV at the Anderson Readiness Center, which the military will own. Also part of the project are two 800kW diesel generators owned by the military department.

In February, the Portland area experienced power outages because of severe weather that left about 200,000 customers in the dark, some for several days.

Before the Oregon Military microgrid was installed and deployed at the Colonel Nesmith Readiness Center, the facility was equipped with 225kW of solar plus the diesel generator. But without a battery and controls, the solar didn’t operate during outages and the diesel generator only provided three days of backup generation, said Sanchez.

Energy Trust of Oregon supplied more than $100,000 in incentives to the project, said Jeni Hall, program manager of advanced solar for the Energy Trust.

In addition to adding resilience, the microgrid is expected to cut diesel use during outages by 50%, resulting in $2,100-$3,700 a month in savings, said Chris Johnson, CEO of Blue Planet Energy. Load shifting and demand charge management are expected to save the military department about $2,000 a year.

Among the challenges of getting the microgrid deployed were electrical codes that require the diesel generator to operate more often than hoped for, said Sanchez. These codes prevent the diesel generator from supplying power to the battery, which would reduce diesel use.

At issue are National Electrical Code requirements that apply to the emergency panel that was located at the facility before work on the microgrid began. The panel is associated with the diesel generator.

Emergency panels are generally required in buildings that serve large numbers of people — hospitals, for example. They can provide power for ventilation, exit signs, sprinkler systems, fire detection and industrial processes whose interruption would spark safety issues.

“If you’re dealing with a facility legally required to have an emergency panel, there are a whole set of rules,” said Sanchez.

“This is common. We couldn’t tie the diesel generator to the energy storage system, so the diesel generator has to run more often and use more fuel anytime there’s an outage.”

This is because the storage can’t take advantage of any extra energy production available when the diesel generator is running. The storage system can only rely on solar and storage.

When the sun is shining, the system uses solar and storage first. Once the energy storage is depleted at night, the system uses diesel.

As part of the planning process, Mayfield Renewables looked at how loads would change during disasters.

“What if energy use was double or triple? We looked at how much fuel would be used in those cases,” said Sanchez.

Mayfield Renewables also evaluated the benefits of peak shaving and demand management with energy storage. Peak shaving will generally be accomplished by discharging the battery daily during peak hours, which generally occur early in the morning, around 7am, before the solar kicks in. Without the peak shaving, the Oregon Military Department would pay higher demand charges.

Blue Planet’s storage system can be scaled and uses a ferrous phosphate chemistry that’s less susceptible to thermal runaway than other chemistries, said Blue Planet’s Johnson.

The batteries last longer and don’t degrade as much when cycling. While the Blue Planet systems are more expensive upfront, their expected life is longer than other batteries — about 20 years — and operating costs are lower, he said.

The project was 33 months in the making because of the complex nature of the installation, including the need for permitting and waiting for the utility, Pacific Power and Light, which serves the Nesmith Readiness Center, to approve interconnection.

“We played the role of pushing the project through,” said Sanchez. “Every time we encountered a barrier, we had to figure out a way around it.”

This article was originally published on Microgrid Knowledge. Reproduced here with permission.