SAN JUAN, Puerto Rico -- In a continuing mission to restore critical electrical power to the people of Puerto Rico, Task Force Power Restoration, U.S. Army Corps of Engineers, is using microgrid technology to temporarily power areas that were hit hardest by Hurricane Maria.Capt. Aaron Anderson, TF Power Restoration, is the operations officer leading the effort, along with key partners FEMA, USACE Recovery Field Office's temporary emergency power mission, and Puerto Rico Electric Power Authority."A microgrid can take many forms," said Anderson. "We are taking one or more 1,850 kilowatt generators, the huge ones you find powering hospitals and big box stores, and with the use of transformers, set up at a site. We then hook directly into PREPA infrastructure through a substation or directly into the main grid, and push power to a variety of facilities that are on the line that haven't been damaged and can accept it."To date, Anderson's team has set up microgrids in five locations, starting with Culebra Island. The next four were placed in the southeast part of the island, which sustained tremendous damage when Hurricane Maria made landfall. Those microgrids are operating in Patillas, Maunabo, Naguabo and Yabucoa. "We are now looking more into the central portions of the island, and the potential for some of those mountain villages," said Anderson."Once we complete our assessments to make sure that the grid is good enough to accept power, and what types of facilities are on that system, we then go out and install these semi-trailer-sized generators," he continued. "This initiative helps us do multiple things: get power quickly and more efficiently to a lot of homes, businesses, and critical facilities, but it also allows us to look at those facilities that are down range that already have smaller generators on them."We can get those generators back and put them where needed. With two large generators on a microgrid configuration, I may be able to get back 8, 9 or 10 smaller ones for use elsewhere."This critical mission may not have taken root, if not for an administrative oversight.Anderson, a civil works project manager with the Portland District, arrived here a week after Thanksgiving Day, on Nov. 28, 2017. He was originally slated to be a battle captain for South Atlantic Division (Forward)."Someone had arrived and taken that position three hours before me. So I was technically excess," said Anderson. "They brought me here and Task Force Commander Col. John P. Lloyd was ecstatic to have another captain on his staff. So he made me an operations officer."During our first sit-down, he looked at me and said, 'Hey, we've been talking about this microgrid effort; go do microgrids.' Later that day, we were fortunate to attend a meeting where people from FEMA that I needed to work with on microgrids were on hand. We performed a mind meld and the mission took off from there like wildfire." It didn't take long before the team realized that as the power grid restoration was ramping up to bring the main power back to the people, there were some gaps."We were putting in smaller generators at critical facilities, but we still knew there were areas of the island that weren't going to see power restoration for some time," Anderson said.A 2008 West Point graduate, Anderson has two master's degrees: Engineering Management, Missouri University of Science and Technology, and Civil Engineering, University of Michigan. He hails from Muskegon, Michigan, and he and wife Kate have a two-year old daughter, Elizabeth. Anderson's academic, project management and overseas field operations experience and versatility, including a tour in Afghanistan as a forward operating base mayor, have prepared him well for this critical mission. "Throughout this mission, PREPA has been a great partner. They're 110 percent behind this initiative," said Anderson. "It's their system, so we have the ability to put the microgrid in place and install the transformers, and when we go from our system into theirs, PREPA performs those connections. So they are fully on board. They also provide the operators for the system."FEMA is the approval authority, said Anderson. "So when we meet with the local government, when we meet with that local mayor, we get our rights of entry and other required legal documents, and FEMA is a major partner in that process. They also help us prioritize each system and where it should go next."It's hard to determine the exact amount of people who have their power restored through microgrids, said Anderson. Microgrids take time to develop because PREPA does a lot of switching, and they have to find the faults in the system. "Looking at the population of the five towns where we've installed the microgrids, we estimate we are serving about 95,000 people," said Anderson. "That doesn't mean 95,000 people necessarily have power; now their town has power. The aim is that their grocery store now has power; they now have a town emergency center that can issue them assistance; 95,000 people are going to directly benefit from these microgrids." Now that the team has more systems on the ground, they are getting more recommendations for future systems. "At first, it was an unknown capability -- people didn't realize we could bring it to Puerto Rico -- and so once we began putting in systems a lot more mayors heard about it," said Anderson. Anderson said the team is very selective because they must make sure they have the right systems in place to meet specific needs. They draw upon the local knowledge of FEMA's liaison officers and local folks on the ground; they talk to mayors and find out where are the best places to put these systems. "We want to find the towns that have the greatest need; who's going to be without power the longest; who needs critical facilities brought back online," said Anderson. "From there, we bring those recommendations to PREPA, which then comes back with theirs. We look at all of them and decide what the priority order will be as a group. From there, we go out and conduct assessments."An assessment doesn't necessarily mean the team is going to install a microgrid system. Instead, an assessment determines if installing a microgrid is still a viable option. If all of the team's criteria are met, then they move forward."If it doesn't fit our criteria, maybe we can refer the candidate to non-governmental organizations or private industry groups that may have alternate solutions, such as smaller generators, solar or wind," said Anderson. "The microgrid systems we install are very costly and in limited supply."The team is currently performing an analysis to determine if they want to make another request to the mainland to have more microgrid systems shipped here. A lot of that is driven by more folks on the island to do grid restoration, said Anderson."Microgrids are a great tool to help us service areas where main grid restoration is not projected to be complete in the near term," said Lloyd. "Microgrids allow us to proof a distribution system in an area prior to main grid restoration so that when grid power is restored, there is less time spent having to diagnose the lines. The system is also very versatile, and may be a capability that can be used in future storms throughout the region." Army Chief Warrant Officer 5 Thomas Black, from U.S. Army Pacific Command, Hawaii, has been here since Dec. 9, 2017, providing subject matter expertise in the planning, installation and management of the microgrid operations on Puerto Rico. The 37-year-old Army veteran wishes that microgrid installation had started earlier, because this temporary power initiative is paying huge dividends."Not having power at your house does not stop it from being your home. But, when you lose power in a town, the town starts to fade, and if it goes on too long it may never go back to what it was," said Black. "Bringing power to these towns that may have had to continue to go without, gave them a chance to rebuild before they lost even more."Anderson is set to redeploy home Jan. 7 to reunite with family and resume his district mission. He'll also resume his weekly fitness regimen, which includes ultra-marathons, Iron Man triathlons and daily cross-training."Departing is always bittersweet for me," said Anderson. "You've made an investment into this mission, but you're so excited to go home, to see family, to reconnect, and to get back to life back home. It's really been a pleasure to be down here, and I don't look at this as work. I've been blessed with the opportunity to turn lights on and help people; especially citizens who haven't had power for 90, 100 days. That's something that lasts a lifetime; something you never, ever forget."I want to be put out of a job. That means the main grid power in Puerto Rico is back online."