Providing power to the hospital through the use of solar cells requires a knowledge of multiple engineering disciplines. The cells use Einsteins photo-electric effect to convert the energy carried by photons of light into direct electrical current (DC current). The electrical current must be large enough to adequately supply the power demand of the electrical devices and it must be converted into a waveform that can be used. This is where the student volunteers come in, in order to determine the proper system sizing we must determine the electrical load that will be consumed by researching the power consumption of each device. We then use these numbers to calculate the amount of solar cells to be purchase based on the output of each cell and the amount of sunlight that each cell will be exposed to in a given day. Additionally, we must convert the DC current from the cells into alternating current (AC current) to power the microscope, centrifuge, and refrigerator. This is done by using a power electronic device called the inverter. Besides powering the hospital equipment, the current will be used to charge a battery bank that will act as power supply when there is inadequate sunlight. Other considerations must be given to module "racking" (fitting the solar cells to the roofs) and electrical wiring. For these tasks, we will imitate methods developed on previous trips.
The high solar irradiation index for Africa is provided below. This figure demonstrates the potential for Photovoltaic energy production throughout Africa.
