Below is a list of frequently asked questions about solar for your business or home. Are there other things you’d like to know about solar?
What is photovoltaics (solar electricity) or “PV”?
What do we mean by photovoltaics? The word itself helps to explain how photovoltaic (PV) or solar electric technologies work. First used in about 1890, the word has two parts: photo, a stem derived from the Greek phos, which means light, and volt, a measurement unit named for Alessandro Volta (1745-1827), a pioneer in the study of electricity. So, photovoltaics could literally be translated as light-electricity. And that’s just what photovoltaic materials and devices do; they convert light energy to electricity, as Edmond Becquerel and others discovered in the 18th Century.
Why are the environmental benefits of solar energy ?
Solar power, like other renewable energy resources, has many environmental and health benefits. Going solar reduces greenhouse gas emissions, which contribute to climate change, and also results in fewer air pollutants like sulfur dioxide and particulate matter, which can cause health problems.
How can we get electricity from the sun?
When certain semiconducting materials, such as certain kinds of silicon, are exposed to sunlight, they release small amounts of electricity. This process is known as the photoelectric effect. The photoelectric effect refers to the emission, or ejection, of electrons from the surface of a metal in response to light. It is the basic physical process in which a solar electric or photovoltaic (PV) cell converts sunlight to electricity.
Sunlight is made up of photons, or particles of solar energy. Photons contain various amounts of energy, corresponding to the different wavelengths of the solar spectrum. When photons strike a PV cell, they may be reflected or absorbed, or they may pass right through. Only the absorbed photons generate electricity. When this happens, the energy of the photon is transferred to an electron in an atom of the PV cell (which is actually a semiconductor).
With its newfound energy, the electron escapes from its normal position in an atom of the semiconductor material and becomes part of the current in an electrical circuit. By leaving its position, the electron causes a hole to form. Special electrical properties of the PV cell—a built-in electric field—provide the voltage needed to drive the current through an external load (such as a light bulb).
How big a solar energy system do I need?
The size of solar system you need depends on several factors such as how much electricity or hot water or space heat you use, how, the size of your roof, and how much you’re willing to invest. Also, do you want the system to supply your complete energy usage or to supplant a portion of your higher cost energy usage? You can contact a system designer/installer to determine what type of system would suit your needs.
Why should I purchase a PV system?
People decide to buy solar energy systems for a variety of reasons. For example, some individuals buy solar products to preserve the Earth’s finite fossil-fuel resources and to reduce air pollution. Others would rather spend their money on an energy-producing improvement to their property than send their money to a utility. Some people like the security of reducing the amount of electricity they buy from their utility, because it makes them less vulnerable to future increases in the price of electricity.
If it’s designed correctly, a solar system might be able to provide power during a utility power outage, thereby adding power reliability to your home. Finally, some individuals live in areas where the cost of extending power lines to their home is more expensive than buying a solar energy system.