PHOTOVOLTAIC APPLICATIONS Jiyeon HYUN

What is photovoltaic ? Photovoltaics are best known as a method for generating electric power by using solar cells to convert energy from the sun into a flow of electrons.

Advantages the highest power density among renewable energies It can be used for long time. (40years) Reduce pollution Disadvantage s Wide places is needed. Initial cost is high

Principal

N type of silicon / P type of silicon - silicon has for valence electrons, all of which are normally part of bonds in a silicon crystal. - an atom such as phosphorus, having five valence electrons. (n type) - An impurity atom with three valence electrons (such as boron) would sit in the position of the original silicon atom (p type) principal

Light incident on the cell creates electron-hole pairs, which are separated by the potential barrier, creating a voltage that drives a current through an external circuit. principal

PV system types GRID-TIE (BATTERY FREE) GRID-TIE WITH BATTERY BACKUP STAND-ALONE PV DIRECT

GRID-TIE (BATTERY FREE) This system does not provide backup power during a power outage (even if the sun is shining) but for sites with reliable grid power, this is usually the logical system choice.

GRID-TIE WITH BATTERY BACKUP It can also push excess electricity produced to the electric utility grid but has the added feature of batteries in order to power some selected backup loads when the grid is down.

STAND-ALONE The Off-Grid or Stand-Alone PV System incorporates large amounts of battery storage to provide power for a certain number of days (and nights) in a row when sun is not available.

PV DIRECT PV Direct systems are usually very simple systems where the photovoltaic panel is connected directly to a motor or pump which matches the voltage and amperage output of the panel.

conference aicshttp://en.wikipedia.org/wiki/Photovolt aics pdfhttp:// 448.pdf rect=Log&logNo= http://blog.naver.com/kunastory?Redi rect=Log&logNo= ms.htmlhttp:// ms.html

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