In step with the U.S. military’s latest energy priorities, Charlotte-based Duke Energy just declared its plans for a self-sustaining microgrid – powered by solar and batteries – that will provide backup electricity to a National Guard facility.
The only problem, from the point of view of North Carolina clean energy leaders: the project will be built in Indiana.
The announcement continues a trend the leaders decried recently at a forum in Wilmington: only military installations outside the Tar Heel state excel in meeting energy priorities handed down from U.S. Department of Defense.
Still, many of those who gathered last week for a roundtable discussion of the military and energy hope change is on the horizon – thanks to the state’s growing number of microgrids and a sweeping new energy law adopted this summer.
A new focus on resilience
The nation’s largest energy consumer, the U.S. military has long prioritized curbing energy use and developing renewable energy for practical reasons: supply of wind and sunshine are infinite and less vulnerable to attack, and distributed energy generation provides security against disruptions to the wider electric grid.
North Carolina has the second most solar capacity in the country, and also the third most uniformed military personnel. But with only one major solar array at Camp Lejeune – a Marine Corps training base along the coast – the state’s installations do little to reflect the military’s past goal of 25 percent renewable energy by 2025.
And now, according to the military leaders gathered at the Wilmington “Southeast Region Military Energy and Environmental Roundtable,” there’s a new priority: resilience.
“Our ability to be able to defend our nation fundamentally depends on reliable energy at our military installations,” said Tad Davis, a Department of Defense official in charge of energy issues, in a keynote to the assembly. “Our intent as we look at the whole spectrum [of energy sources] is not to limit ourselves.”
Asked later if that meant the Trump administration was abandoning the aim of 3 gigawatts of clean energy – about as much solar power installed across North Carolina today – a spokesman said, “the … goal was an informal Department of Defense target.”
“Our current policy is focused on deploying the most cost-effective energy solutions – regardless of technology type – that can directly benefit both the mission and resiliency of our installations,” Department of Defense spokesman Adam Stump said in an email.
Can solar serve the goal of resilience?
The new focus on resilience – the ability to prepare for and recover from power disruptions with minimal impact – is particularly relevant to the six major military installations in North Carolina’s low-lying coastal plain, where hurricanes make frequent landfall. And experts say the state’s leadership in solar energy is still valuable – since resilience and clean energy aren’t mutually exclusive.
“Microgrids and energy storage would tend to be something that we should consider under the banner of resilience,” said Diane Cherry of the North Carolina Sustainable Energy Association, which sponsored last week’s forum with the Environmental Defense Fund and state agencies.
Case in point: in July, tourists were forced to evacuate the state’s Outer Banks when construction crews accidentally severed a transmission line, cutting off the power supply to the barrier islands. Ocracoke Island, however, kept the lights on for residents using its microgrid: a self-sustaining power grid that includes a Tesla battery pack, 62 solar panels, and a diesel generator.
“The solar worked,” said Heidi Smith of the Tideland Electric Membership Corporation, which runs and owns the microgrid. “The Tesla batteries were able to add power to the system.”
Davis said many existing military-backed renewable projects could serve the goal of resilience. But right now, solar projects – like the one at Camp Lejeune – simply deliver renewable energy to the larger electric grid without the ability to provide backup power to bases.
“From a resiliency stand point we want to kind of turn that around,” Davis said at the forum.
Progress, challenges ahead for energy storage in North Carolina
Duke Energy spokesman Randy Wheeless said that was just the plan for the 17 megawatt Lejeune project, which the utility owns. “Really the next step…is islanding the base using renewables to get them to a full-fledged microgrid,” he said.
At the roundtable, a representative from Arizona Public Service touted a diesel-backed microgrid project on a Marine Air Corps station, in part as a cost-effective means of meeting peak electricity demand.
Duke, on the other hand, has three microgrid projects underway in North Carolina – all made up of solar power and battery storage. “What we’ve been working on over the past few years is the green microgrid concept,” Wheeless said.
The company also has two other major storage projects planned: a 9 megawatt project in Asheville and a 4 megawatt project in Hot Springs – both part of the 75 megawatts of storage it plans for the next 15 years.
Duke and clean energy advocates value microgrids and energy storage for their resilience as well as for other benefits: they can avoid costly new infrastructure, reduce spikes in demand, and complement renewables.
A sweeping new energy law adopted this summer requires research into how utility regulators can best quantify these advantages, and potentially incentivize more microgrids and storage projects. But its results aren’t expected for another year.
Until then, even in light of the military’s focus on resilience, advancing storage will be a challenge, says Cherry of the Sustainable Energy Association.
“It will take an enormous amount of leadership,” she said.