Solar power is a term that refers to several alternative sources of energy by which sunlight is harnessed to do useful work for mankind. People know that it is energy since the name alone implies this, but many people think it is expensive and not a preferred method of producing energy. We need to find out how cost effective it is how efficient it is, its many uses and whether it is affected by the weather.
One of the most useful solar power technologies involves the use of Photovoltaic cells, which true to their name (photo = light, voltaic = electricity), convert sunlight directly into electricity when light strikes the Photovoltaic cell. A portion of the light is then absorbed within the semiconductor material in the cell. When the absorbed light is transferred to the various layers of the semiconductor, the transferred energy breaks the bond between electrons and the semiconductor atoms. This allows the electrons to flow freely. PV cells can have one or many electric fields that force electrons to flow in a certain direction. The flow of electrons is called current, and by placing metal contacts on top and bottom of the PV cell, we can then use that current externally. ("How Solar Cells Work").
How cost effective is solar power? That depends upon the design of a PV system. However, kilowatt-hour for kilowatt-hour, the cost of PV energy is still generally higher than energy bought from your local utility company. For example, at the present time a PV system costs approximately $22k to install the system. That would be $1100 a year and an average of $91 a month for 430kw hours per month over the course of 20 years. We should keep in mind that the PV system would supply all the electricity needed for a fairly small home. Lets compare this to the local utility charges. The monthly charge for 433 kw hours per month is$36. This would average $432 a year. But "Batteries add a lot of cost and maintenance to the PV system" (How solar cells work.
