Solar Energy - FAQ
Q: What is solar power?
A: Solar power is the conversion of sunlight into electricity, either directly using photovoltaics (PV), or indirectly using concentrated solar power (CSP). CSP systems use lenses or mirrors and tracking systems to focus a large area of sunlight into a small beam. PV converts light into electric current using the photoelectric effect.
Q: What is photovoltaics and how does it work?
A: Photovoltaics is the field of technology and research related to the practical application of photovoltaic cells in producing electricity from light, though it is often used specifically to refer to the generation of electricity from sunlight. Cells can be described as photovoltaic even when the light source is not necessarily sunlight (lamplight, artificial light, etc.). In such cases the cell is sometimes used as a photodetector (for example infrared detectors), detecting light or other electromagnetic radiation near the visible range, or measuring light intensity.
The operation of a photovoltaic (PV) cell requires 3 basic attributes:
- The absorption of light, generating either electron-hole pairs or excitons.
- The separation of charge carriers of opposite types.
- The separate extraction of those carriers to an external circuit.
Q: How much power will solar generate?
A: Power output is determined by the size of the system and solar irradiation in the area. Solar panels are usually installed in areas with many stable sun hours per day. For example, an installation for residential use in Germany generally requires 5 kW to provide stable output for an average household for one year. The current U.S. national average of homes powered by one MW of solar is 164.
Q: Can a solar installation produce electricity on a cloudy day?
A: Since the electricity generated depends on light intensity and not irradiation or direct sunlight, it will produce electricity in cloudy conditions. However the greater the intensity of the light, the greater the flow of electricity. Hence you generate more on sunnier days.
Q: Will using more solar energy help to prevent global warming?
A: Yes, carbon dioxide is main greenhouse gas responsible for negatively effecting the changes in the world's climate. Major contributors of carbon dioxide emissions are fossil fuel energy plants. According to experts, in order to avoid a dangerous level of climate change we must cut our carbon dioxide emissions by 80 to 90 percent by 2050. While we will constantly require sources of energy, it is pressing we look to cleaner sources that don't produce carbon dioxide. Solar power is a clean, renewable form of energy that produces zero emissions of any kind.