Solar Cells and Solar Systems

Solar cells are produced from raw silicon materials in a multistage process. Firstly raw quartzite sand is processed into bulk silicon, which is subsequently melted and formed into blocks or ‘ingots’. The ingots are cut and sliced to produce ‘wafers’ which form the basis of a solar cell. Solar cell manufacturers (such as Jetion) add electrodes to the wafer for electrical connectivity. The wafers are then cleaned and treated prior to their introduction into the manufacturing process.

Solar cells are usually mounted in large arrays known as ‘solar modules’ electrically interconnected and sealed under toughened glass to protect them from the weather. Solar modules, together with various system components such as batteries, charge controllers and inverters, form the basis of a complete solar power system.

Solar power systems can be connected to the electricity grid or used in isolated units, as ‘off-grid’ power. When electrical grid connection is possible, any excess electricity can be fed back into the system and sold. Off-grid systems are found where grid access is physically difficult or economically unattractive, such as portable, remote, off-shore locations or developing countries.