Overview

Photovoltaic Introduction

Photovoltaic (PV) cells are made from semiconductor of which two types, crystalline silicon and thin film, are currently most popular. The latter is divided into amorphous and CIGS. A comparison between the two main types of PV is shown below:

Types of  PV cells
Primary Materials
Light Absorption Characteristics
Stability of Power  Generation
Efficiency
Thin Film
(CIS/ CIGS)
Copper Indium Gallium Selenide(CIS/CIGS)
Compound of Copper, Indium, Gallium, Selenium
Wide Spectral Range
High Stability,  Low Degradation
9~12%
(CdTe)
Cadmium Telluride
Compound of Copper, Indium, Gallium, Selenium
Wide Spectral Range
High Stability,  Low Degradation
8.5~10.5%
Amorphous
Silicon
Limited Spectral Range
Degradation
5~8%
Crystalline Silicon
Monocrystalline
Silicon
Limited Spectral Range
Degradation
15~18%
Polycrystalline

While crystalline silicon PV is currently the most common type due to its longer history of development, recent raw material shortages and resulting price fluctuations have led to unstable production costs. While, in the lab, gallium arsenide provides the highest efficiency rate, its high costs render mass production impractical. Moreover, crystalline silicon PV has limited light absorption capabilities, meaning that its power generation is relatively short in duration (Note 1), and is furthermore accompanied by degradation(Note 2). These factors work to temper the seeming advantages of crystalline siliconPV.

AxunTek’s proprietary research as well as mass-production of CIGS thin film photovoltaic integrates the best recipe of copper, indium, gallium, and selenium.  Our products are characterized by excellent absorption rate, high stability, high efficiency, high yield, low production cost, and short energy payback time. CIGS photovoltaic is the brightest star in solar energy today, going head to head with silicon cells.


Note 1: The light spectrum is divided into visible, infrared, and ultraviolet regions. Crystalline silicon and amorphous silicon PV can absorb light within the 400-700nm wavelength. CdTe and CIGS PV absorb light not only in the visible range, but also in the 700-1,200nm infrared range. Thus, after absorbing the same day’s worth of light when compared with silicon-based cells, cells made from these materials can subsequently give off energy for longer periods of time.
Note 2: Different materials exhibit varying energy-emitting qualities following exposure to sunlight. Both crystalline silicon and amorphous silicon PV exhibit degradation following long-term exposure to strong light, which reduces their ability to generate electricity.