Solar Energy, Cells

Abstract- Solar energy which uses light and heat from the sun for its energy generation. For a long time it has been known to be renewable, clean, inexhaustible, and environment friendly, this energy from the sun could be harnessed with a wide range of ever-evolving technology which include concentrating photovoltaics, non- concentrating photovoltaic, solar heating, solar thermal energy etc.

A proper understanding of these technologies cannot be underestimated in solar energy power and electricity generation considering the ever increasing rate of industrialization and fast and quick depletion of fossil fuel resource all over the world.

Key words: PV, photovoltaic, solar energy, cells.

I INTRODUCTION Photovoltaic

In 1870, Heinrich Hertz studied photovoltaic effect on solid like selenium, after a while selenium cells were produced and were able to convert light to electricity with over 1% efficiency. Selenium was later adopted for use in the field of photography and incorporated in light measuring devices.

Steps were taken in 1940s and early 1950s towards commercializing pv and the czochralski process was created for producing crystalline silicon which were highly pure. About 1954 at bell laboratories, scientist improved on the czochralski process and they developed the first crystalline silicon photocell with an efficiency of about

Technology Description

1. Solar photovoltaic (PV) Solar photovoltaic (pv) system compose of solar panels which contains a number of semi conductor solar cells in array which in turn converts the sun rays to electricity which is actually done without moving any of its parts and also without producing air pollution, fuel wastes or green house gases. Fig 1 The panels in the pv convert solar energy into electricity. Output power is dependent on the volume of energy incident on the cell surface and also the operating temperature. Three types of pv cell technology were first discovered.

*Mono crystalline: these cells are produced from a single crystal. The production methods are difficult and expensive. These tend to be more efficient and more expensive.

*Polycrystalline: The production process allows multiple crystalline structures to develop within the cell. It is relatively cheaper than mono crystalline but has lower efficiency. *Thin-film: Uses less silicon to produce the cell allowing for cheaper production costs. It tends to be less expensive but has also lower efficiency.

Fig 2