Seabees Bring Sustainable Energy to Africa
In a remote village with constrained resources, the simplicity of a new energy system is what ensures it will stay maintainable…and dependable.
By Lt. j.g. George Fischer, CEC, USN, M.SAME, Chief Mass Communication Specialist Jesse Sherwin, USN, and Construction Electrician 1st Class James Ingram, USN
Is it possible to combine renewable energy technology with effective mission accomplishment on the strategic and tactical levels? That would be a good question to ask the U.S. Navy Seabees of Naval Mobile Construction Battalion (NMCB) 3, because they recently finished installing a 6-kW photovoltaic power system at a school in the remote village of Kontali, Djibouti in Africa.
As an expeditionary element of the U.S. Navy, a Detail of Seabees was assigned to Combined Joint Task Force – Horn of Africa (CJTF-HOA). Their mission was to help promote regional stability, dissuade conflict and protect U.S. and coalition interest in the region by providing humanitarian assistance to distant and isolated areas of Africa. Kontali, Djibouti is one such region.
It was necessary then, for NMCB 3, in a seemingly straightforward mission to develop an energy system for a local schoolhouse to also determine an asset management approach that would enable the facility, given its myriad logistical challenges, to be effectively self-sufficient. The Seabees not only wanted to build something that made a difference—they wanted to build something that would last.
Approximately 1,000 people in Kontali live without any power. The closest city with power is Dikhil, Djibouti, some 10-mi away. Such a distance makes the costs prohibitive to supply traditional power.
The pre-existing schoolhouse in Kontali was over-crowded and the people of the village deserved a longer-term solution. The predicament of powering a place of learning in a poor, remote village in the Horn of Africa presented a great opportunity for a humanitarian assistance project and a chance to establish an energy system that would take into account a sustainable lifecycle of the schoolhouse and planned future additional buildings. CJTF-HOA tasked the Seabees with building a new school to serve the Kontali community.
Although building a school should be a fairly routine task, providing the energy source that the facility required was the challenge. Because of the remote location of the school and lack of traditional power sources, an innovative idea had to be utilized for the area—a photovoltaic power system. This renewal energy source was just the answer to harness the required power to serve the proposed school house as well as future infrastructure improvement options such as medical clinics and potential expansion for this school and others in the area.
This photovoltaic power system included all aspects of electrical power: generation, transmission, and distribution. This system was used to convert the sun’s solar radiation into electricity via 30 photovoltaic modules (solar panels) that were arranged within five solar arrays. These arrays provided 1.4-kW of power at a current of 60-A with 24-V of potential energy. The electric charge derived from these solar arrays were then stored in a battery bank, which included 40 batteries of 24-V each. To ensure successful transmission, the photovoltaic power flowed from the arrays through the solar string combiner box and into charge controllers, which combine the array current inputs into one output and regulate the charge to the battery banks. Each of the two battery banks consisted of 20 batteries that were arranged in stacks. Each stack had two batteries wired in series to provide the proper voltage and each of the 10 stacks was wired in parallel to provide more amperage. This gave the system the 24-V and 60-A needed for the photovoltaic system to maintain the demand coming from the school.
The photovoltaic system generated direct current but the schoolhouse required alternating current to power its lights, fans and power receptacles. Therefore, the battery power was converted from direct to alternating current via a power inverter and then distributed to the three, 22-ft by 27-ft classrooms—which each had six fluorescent light fixtures, two fans and one 220-V power receptacle. The total inverter output was 6-kW, 220-V, 27-A, 50-Hz single phase; that was sufficient power to meet the electrical load requirement of this schoolhouse and provide a greatly improved education experience for the children of Kontali.
SIMPLE TO MAINTAIN
The system itself actually is very simple to install. The more difficult challenge in building it was shipping all of the components to the remote site in Africa. Each of the parts came from a different contractor and some of the items had long lead times
Basic maintenance of the photovoltaic system is relatively uncomplicated. School administrators in fact can manage most of it easily. While the arrays must be kept clean and the panels will need to be replaced if they are broken, the system itself should be completely maintenance-free for several years. Such a factor of the planning approach will be critical to the schoolhouse’s sustainability, and longevity.
Moreover, any required maintenance of the photovoltaic power system will be worked through the U.S. Forces Civil Affairs Team and the Djiboutian military and leaders for the region. The U.S. Forces Civil Affairs Teams provide critical expertise to host-nation governments and are also able to assess need for critical infrastructure projects such as roads, clinics, schools, power plants and water treatment facilities. They will also provide support in obtaining assistance and needed training for the upkeep of such projects.
With the knowledge of the functionality and capabilities of the solar power system, the local populace can know they have the power available in an area where it was not previously thought feasible. With an average of 10 hours of sunshine every day and 332 sunny days per year, the solar power option will prove to be a valuable alternative. Because many of the villages located in Djibouti are remote, the feasibility of tying into a traditional power source is restricted due to the high costs and limited infrastructure. A self-contained solar-electric power system can mean the difference for a medical clinic or school having power.
BUILT TO LAST
This solar-electric power system was built per international building code standard and only took 50 man-days to complete. It was the pinnacle of the entire 2,857 man-day project on which many different Seabee teams worked while deployed. This fairly straightforward system may have been a small task compared to the rest of the construction, yet it was key to making the school usable and improving the children’s education experience. The foresight of incorporating a solar-powered energy system for a facility that sees 332 sunny days per year was an effective and efficient use of one of the actually abundant resources that were available in this part of the world.
And while helping supply a self-sufficient schoolhouse to a remote village was one mission accomplished, aside from the school and the solar-electric power system, the many Seabees that worked on this project built something even more important than a school: They built a relationship with the people of Kontali. Seabees are passionately welcomed everywhere throughout the Dikhil region. They have the unequivocal support of its political and military leaders and have demonstrated American goodwill in a way that is tangible to these people.
The Seabees, continuing their fundamental “Can Do” tradition, made it possible to combine renewable energy technology with effective mission accomplishment on the strategic and tactical levels. They not only facilitated building improvements to a local school, they made a long lasting relationship of goodwill with the people of Kontali. That is true lifecycle planning.