06-10-2012, 03:11 PM
Solar Technology
[attachment=35529]
Monocrystalline Silicon
are made of silicon wavers cut from one homogenous crystal in which all silicon atoms are arranged in the same direction. The monocrystal is manufactured using the "CZOCHRALSKI GROWTH TECHNOLOGY". Hereby a round bar of silicon is drawn with a speed of a few centimeters per hour from pure molten silicon.
Polycrystalline Silicon
are poured and are cheaper and simpler to make than monocrystalline silicon. Whilst setting the different crystals are formed that give the material its characteristic flaky blue metallic color. The efficiency of multicrystalline cells is however somewhat less than that of monocrystalline cells.
Amorphous Silicon
are made with help of a deposition technique, like plasma deposition. These are called amorphous silicon Cells, which are relatively cheap, but with low efficiency. "AMORPHOUS" means: No crystalline structure. III/V solar cells are cells with a high efficiency, but are made of very expensive semi-conducting materials. Furthermore there are various types of thin film polycrystalline cells and cheap organic cells.
New Methods
Surface Structuring
Tandem Cell
Concentrator Cell
Gratzel Cell
MIS Inversion Layer Cell
Lower cost substrate
New Methods – Tandem Cell
Different semiconductor materials will be arranged one on top of the other to decrease the amount of energy lost during absorption. The cells are arranged so that they are in descending order in terms of band gap (Eg).
New Methods – Lower Cost Substrate
Still using Silicon wafer based
Thickness around 10-30 microns
This is 10 times thinner than current wafers
Processed in lower temperature
Needs light trapping because:
- Impurity interaction with the foreign substrate
- Partly due to imperfect crystallinity and structural defects.
Solution to have light trapping feature is to have Si films with large grain size.
Conclusion
Inventor of first solar module is Charless Fritts
Types of solar cells with current technology: monocrystalline, polycrystalline, and amorphous silicon
New methods: surface structuring, tandem cell, concentrator cell, Gratzel cell, MIS inversion layer, lower cost substrate
New Materials: copper indium diselenide, and cadmium telluride
[attachment=35529]
Monocrystalline Silicon
are made of silicon wavers cut from one homogenous crystal in which all silicon atoms are arranged in the same direction. The monocrystal is manufactured using the "CZOCHRALSKI GROWTH TECHNOLOGY". Hereby a round bar of silicon is drawn with a speed of a few centimeters per hour from pure molten silicon.
Polycrystalline Silicon
are poured and are cheaper and simpler to make than monocrystalline silicon. Whilst setting the different crystals are formed that give the material its characteristic flaky blue metallic color. The efficiency of multicrystalline cells is however somewhat less than that of monocrystalline cells.
Amorphous Silicon
are made with help of a deposition technique, like plasma deposition. These are called amorphous silicon Cells, which are relatively cheap, but with low efficiency. "AMORPHOUS" means: No crystalline structure. III/V solar cells are cells with a high efficiency, but are made of very expensive semi-conducting materials. Furthermore there are various types of thin film polycrystalline cells and cheap organic cells.
New Methods
Surface Structuring
Tandem Cell
Concentrator Cell
Gratzel Cell
MIS Inversion Layer Cell
Lower cost substrate
New Methods – Tandem Cell
Different semiconductor materials will be arranged one on top of the other to decrease the amount of energy lost during absorption. The cells are arranged so that they are in descending order in terms of band gap (Eg).
New Methods – Lower Cost Substrate
Still using Silicon wafer based
Thickness around 10-30 microns
This is 10 times thinner than current wafers
Processed in lower temperature
Needs light trapping because:
- Impurity interaction with the foreign substrate
- Partly due to imperfect crystallinity and structural defects.
Solution to have light trapping feature is to have Si films with large grain size.
Conclusion
Inventor of first solar module is Charless Fritts
Types of solar cells with current technology: monocrystalline, polycrystalline, and amorphous silicon
New methods: surface structuring, tandem cell, concentrator cell, Gratzel cell, MIS inversion layer, lower cost substrate
New Materials: copper indium diselenide, and cadmium telluride