Solar Projects - Lighting
Less than 7% of the entire population of Malawi has access to electricity, and it is unlikely that the remote villages will experience grid based power for many decades to come, if ever. We believe electricity is a critical component of the factors that instill hope and lead to change. Lighting the MOH centers so that children have a place to come at night to read and study was a goal we began in 2010. In 2016, we celebrated bringing solar powered central lighting to Katondo, the 5th and final MOH center without electricity. However in 2018 we will install a solar facility in the 6th MOH center of Mponela, because despite it's grid connection, electricity is seldom available there more than 30% of the time!
Each center has provided its own set of construction challenges, but as villagers became aware of our projects many came to help.
Our core team has worked together the past four years, and is comprised of Daniel, Frank, Peter, and Lamech. They have become skilled in much of the process of building and expanding our solar facilities, so that most of the work is done by them.
Nothing is more rewarding than the follow up photos we receive from the center directors of children gathering to read, and villagers congregating at night for productive activity. We feel we are not only “pushing back the darkness” at these lighted community centers, but also initiating an electrical infrastructure that will create vision, and hope of change.
But it's not just the lighting . . .villagers come to charge their cell phones, and barber shops have even cropped up at two centers. Given the breakthrough of available electrical energy, the center directors and villagers are developing their own ways to improve local life.
To automate our solar installations as much as possible, we equipped each of our installations with a Siemens programmable control (PLC) computer for which we developed a program to control lighting of the centers in the most effective way possible. Lights are prevented from operating during the daytime when the voltage is higher and shorten LED life, batteries are protected from overdischarge, and as the battery charge is drawn down at night, banks of lights begin to turn off to preserve some level of lighting as long as possible. Reserve is maintained for security lighting through the night.
Our "base" installations employ four 140 watt panels to generate 600 watts of power (approx 50 amps at 12 vDC). This is sufficient for lighting at most of MOH's centers. Chimwang'ombe and Matapila centers have larger floor areas, and require greater power generation.
In Malawi, optimal solar radiation is obtained by mounting the panels facing due north, at an angle of approx 12 to 14 degrees. Depending upon the orientation of the center's roof line, panel mounting must be designed accordingly.
Mounting our panel frames to the roof requires adding timber reinforcing to the widely spaced trusses, to withstand the rainy season storms, and provide security. This can require creativity. Years ago we shipped a ladder and rolling scaffold, which are invaluable to all our operations.
We mount the solar panels on the building roofs for security and protection, as well as to maximize unblocked solar exposure, with a secure control and battery center in storeroom below. We manufacture our own custom light fixtures, solar panel frames, and control boxes and circuitry to keep installation cost to a minimum, as well as to accommodate the specific nature of each center.
One young helper at Katondo told us he didn't need a ladder to go back up to add a fitting we had forgotten . . . .
We decided early-on to distribute power at 12 vDC, primarily from a personal safety standpoint considering the hundreds of children at the centers. The rooftop panels generate 24 vDC: we use high quality and reliable Morningstar controllers in all our installations (which we ship from the U.S.), to charge the storage batteries at 12 volts.
Power efficient LED bulbs are used and our custom fixtures are affixed to the underside of the buildings’ open truss framework. As the truss framework of the centers can be as much as 10 feet above the floor, providing sufficient light intensity for reading requires proper bulb selection.
LED bulb selection and fixture design is critically important, not just from an illumination standpoint, but also bulb longevity. Bulb quality is paramount: good quality bulbs cost at least 10 USD, but last much longer than the readily available "cheap" alternatives.
The PVC shrouds keep the bulbs in place and protect them. After premature failures, we found drilling holes provides ventilation (reducing bulb operating temperature by 30 degrees). LED longevity also depends upon operating temperature: lights must not be left on during the daytime when the system voltage is higher to charge the storage batteries!
Why all this attention and hard work? It is almost impossible to fathom the darkness of a Malawi night, where the only light for miles and miles is the glow of cooking fires. Our lighted centers provide oases of hope. . . .
And last, and far from least, the incredible spirit of brotherhood that we all feel after long and hard days working, when the new lights are turned on for the first time. I believe we are all forever changed..
click here to see how we developed a way for villagers to "carry electricity home in a box"
Our custom light fixtures
Programming the Computers?
We were aware that programmable "micro-computers" (PLCs) are widely used industrially to control just about anything, are robust, and are inexpensive (<$80). Alas, the actual programming was an entirely different issue!
While we were considering the possibility of employing PLC's to improve our lighting systems, through an Internet controls forum we came into contact with an industrial electrician, Charles, who generously volunteered to help us with the programming. What a surprise it was to discover Charles worked on a fishing factory ship in the Bering Sea, near the Aleutian Islands of Alaska! It's difficult not to believe this to be God's intervention to solve our problem!