The process that converts solar power into electricity is called the photovoltaic effect. This effect creates voltage when semi-conductive materials react with sunlight. Rays from the sun are comprised of photons that differ in energy amounts, all depending on their wavelength. The photons that don’t pass through the solar cells are either absorbed or reflected when they make contact. The ones that are absorbed are changed from solar power into electricity.
Collecting solar power for electricity is done with the use of solar cells connected together on a larger panel. The most commonly used material is silicon, which is ideal because of the way the valence electrons in its outermost shell react to the valence electrons of phosphorous and boron. Copper indium gallium selenide and cadmium telluride are also popular choices.
Each small cell is made of a thin, semiconducting layer doped with phosphorus on top of a semiconducting base layer doped with boron. Doping is a term that refers to controlled impurities being added to the semiconductor in order to create its conductive properties. The small amounts of boron and phosphorus trade places with the silicon atoms; these create positive ‘holes’ and freely moving, negative electrons, respectively. The positive and negative charges are attracted to each other, and when the particles are drawn onto the neighboring layer by that attraction they generate an electrical field. Sunlight striking this field results in the electrons separating from the holes, which generates the voltage. The photovoltaic effect, put simply, is the act of photons exciting electrons to the point of behaving as charge carriers. The stronger the sunlight hitting the panels is, the more easily the electrons can flow across the layers of the PV cells. Each panel has a limit on the amount of energy it can generate, so most home solar systems are composed of a roof installation of multiple modules. More cells on a rooftop translates to more solar power for electricity being gathered.
When the current is created, it is pushed to contacts located at the front and back of the cell. The circuitry that connects the individual cells conducts this current elsewhere. Electricity is energy made available by the movement of negatively charged particles through conductors, like wires. Direct current (DC) energy, the kind that is created by PV cells, is the flow of electrons in just one direction, and alternating current (AC) energy is made of electrons that can reverse or alternate in direction. Batteries use DC energy and can be employed to store any extra that is produced. AC energy is utilized by electrical power grids. A power inverter is responsible for the conversion of DC energy into the AC energy that is the North American Standard. No hazardous byproducts are created by harnessing this natural, renewable resource. Solar power as electricity provides a diverse array of benefits, ranging from decreased utility costs to shrinking the environmental impact of a home. The generation of energy may be the solution needed to answer the growing demand for energy efficiency.