How Do Solar Panels Work
April 12, 2009 by admin
Filed under Residential Solar Panels
Solar panels are made up of a collection of semiconductor materials that absorb photons. The most common type of semiconductor material used is silicone, which is very plentiful on earth. When photons from the sun strike the semi conductor material of the solar panel they are absorbed by electrons in the silicon semiconductor material. For this to happen, the photons that strike the semiconductor material must be at an energy level of about 1.2. If the energy level is below this minimum, no electricity will be created. About 70% of the photons in sunlight are at, or above this minimum level. The photons with energy levels below the minimum will reduce the efficiency of the solar panel because they create heat instead of electricity and as the panel heats up it becomes less efficient.
Currently solar energy systems still cost more to produce than fossil fuel energy due mostly to costs associated with manufacturing and research but these costs are very quickly dropping due to research and increasing demand. After the initial costs associated with purchasing and installing one of these systems, future costs associated with operation and maintenance are minimal. The lifespan of solar panels is about 20 years and researchers are developing new types of solar panels all the time.
Fossil fuel consumption cannot go on indefinitely because these fuels are not renewable and will eventually become depleted and the next step will be solar and wind power. As the costs of electricity obtained from fossil fuels increase, the cost of installing a system that utilizes solar and wind energy is dropping. In the near future solar power will be the most cost effective source for our heating and electrical needs.
Solar panels generate a steady (DC) voltage and many devices are designed to operate with DC voltage. The typical home is wired for 120 volt AC operation so the DC voltage can be converted to 120 AC voltage using a device called an inverter. It is then available to be used by the power grid in your home.
This reduces the amount of electricity that you will use from the power company. When more power is generated than you need, the extra is automatically diverted out of your house and into the utility companies distribution system and you receive credits for the electricity you provide to the utility. When your solar system can’t provide enough electricity to meet your needs you can then draw from the utility companies distribution system again. This is all done automatically and works very efficiently for both home owner and the utility company.
