How Solar Energy Panels work?
Solar Energy Panels, also commonly called as photovoltaic or PV panels captures sunlight and converts it to DC power. That’s the reason why they are commonly seen mounted on roof top or open field, so that they receive uninterrupted sunlight throughout the day. Solar panel is a collection of solar cells. A large collection of solar cells spread over a large area works together to produce enough electricity to be useful. The more light solar panel receives, the more electricity it produces. That’s the reason why solar panels on spacecrafts are designed in a way that they always point to sun even while rest of the body of the spacecraft moves around. The solar cells that collectively forms solar panels, functions similar to large semiconductor and makes use of large area p-n junction diode. When the sunlight directly strikes these solar panels, the p-n junction diode converts the sunlight to usable electrical energy. When photon (sunlight) strikes the surface of the solar panels, the electrons gets knocked out of its orbit and is released. This forms electric field in the solar cells. The free electron is forced in a single direction and comes in contact of metal in the solar cells and forms electricity. As the number of solar cell grows in the solar panel and the quality of solar cell improves, the total electrical output that a solar panel can produce improves. The process of conversion of sunlight to electrical energy is referred as Photovoltaic Effect.
Solar Energy Panels work works best when it is placed in direct sunlight, away from all kinds of obstructions such as shades and placed in areas with high regional solar insulation ratings. Solar panel efficeincies can even further be optimized with the use of dynamic mounts that are designed to follow the sun’s position in the sky. These dynamic mounts rotate the solar panels to achieve maximum amount of direct exposure of sunlight throughout the day.
Solar cells are laid out in a grid fashion with as many as 72 different solar cells to form PV modules. The module is sealed in an environmentally protective laminate and forms a building block for PVsystems. Multiple PVmodules are assembled together to form solar panels as a pre-wired, field installable unit.
About 80% of the solar panels are made of crystalline silicon solar cells. The rest 20% of the solar cells are made of Cadmium Telluride or CIGS. These solar cells typically cost much less since they can be made in large single sheets. Solar panels are hermetically sealed to protect them. They are then covered in a non-reflective glass to protect the solar cells from environmental damages and are placed in a rigid frame. The frame prevents the structure from deforming due to freezing temperature or from strong winds. The frame also contains provision for drainage hole to prevent water buildup on the panels.
The prices of solar panels have sharply come down recently, majorly due to advancements in technologies and changes brought about in installation techniques. The demand for renewal energy is growing and at the same time improvements in cell efficiency is making solar power competitive.