Various Types of Solar Cell Technologies

1. First Generation Wafer Based Silicon Cells

 Silicon wafer based technology is the oldest and most popular due to its highest power efficiency. First generation solar cells are of two types Mono-crystalline and Polycrystalline solar cell.

1.1. Mono-crystalline Solar Cell

Mono-crystalline cells are made by cutting a block of silicon that has been grown from a single crystal.  These are oldest technology based solar cells. Efficiency of these cells varies from 14% to 17.5%. Performance of these cells is not good at high temperatures but occupies significantly less volume to produce same amount of power. These are two times more expensive when compared to thin film solar cells. Area required for 1 kW solar panel is 6 to 9 m² .

1.2. Poly-crystalline Solar Cell

 Polly-crystalline cells are made by cutting from multifaceted silicon crystal This technology is comparatively an economical choice. Efficiency of these cells varies from 12% to 14%. Similarly as in Mono-crystalline solar cell performance is not good at high temperatures but occupies significantly less volume to produce same amount of power. It is also two times more expensive when compared to thin film solar cells. Area required for 1 kW solar panel is 8 to 9 m² .

2. Second Generation Thin Film Solar Cell

 Second Generation Thin Film Solar Cell cells are much more economical when compared to first generation silicon wafer solar cells. Thin film solar cells are not made up of any crystal. They are made by depositing a thin layer of silicon that is deposited on a base material like metal or glass. Light absorbing layer of silicon wafer cell is around 350 m thick while light absorbing layer of thin film solar cell is quite thin .

2.1. Amorphous Silicon Thin Film Solar Cell

 Amorphous Silicon thin film solar cells are comparatively less costlier and easily available all around. “Amorphous” means there is no definite arrangement of atoms or no definite structure. Temperature performance of these cells is good at both low as well as high temperatures and efficiency of these cells varies from 4% to 8%. These cells require less installation time and require much larger space. Area required for 1 kW solar panel is 13 to 20 m² .

2.2. CdTe Thin Film Solar Cell

 For making a practically economically viable PV system Cadmium Telluride (CdTe) as it is 50% less costlier than conventional silicon cell and it’s efficiency varies from 9% to 11% . Area required for 1 kW solar panel is 11 to 13 m². This cell technology is toxic due to the presence of Cd which is a heavy metal and toxic. Thus manufacturing is limited due to environmental hazards associated with Cd..

3. Third Generation Solar Cells         

It is the new technology that has evolved in the market now-a-days but are not studied deeply.

3.1. Nano Crystal Based Solar Cell

 These are generally known as Quantum Dots (QD). QD refers to the crystal having small size of the order of nano meters such as porous Si. Efficiency of these cells varies from 7% to 8%. These cells have excellent thermal stability and offer a wide range of product designs. It is also 50% less expensive than Si cells and requires less installation time and large space.

3.2. Dye Sensitized Solar Cell

Many studies are going on Dye Sensitized solar cell (DSSC) for improving it’s performance efficiency. These cells use dye molecules between different electrodes. These cells consists of four components – semiconductor electrode, a dye sensitizer, redox mediator and counter electrode. Efficiency of these cells is around 10% and performance is not good at high temperature conditions.

3.3. Polymer Solar Cell

Polymer solar cells (PSC) are flexible in nature because of the presence of polymer substrate. Efficiency of these cells varies from 3% to 10% and performance of these cells is not good at high temperatures. Due to its flexibility it offers wide range of product designs and requires less installation time.

3.4. Concentrated Solar Cell

In Concentrated solar cell (CSC) technology large amount of solar energy is concentrated over a tiny region of a solar cell. The principle of this technology is based on optics. When solar radiations are concentrated on a point, ample amount of heat energy is generated and converted into electricity using integrated power generator. Efficiency of this cell is 40% and offers excellent thermal stability.