Polysilicon
Polysilicon is the photovoltaic material that is used to make a solar panel. The thing about silicon is that it is extremely cheap, but also takes a lot of time and energy purifying it. The process of purification and baking it into photovoltaic material is what polysilicon manufacturers do. There are approximately seven companies that control about 75% of the polysilicon market. Now, with all the solar startup companies, of today, most of them get their material from these seven polysilicon producers:
1- Hemlock Semiconductor (USA)
2- Wacker-Chemie AG (Germany)
3-Renewable Energy Corporation (REC) (Norway)
4-Tokuyama Corporation (Japan)
5-MEMC (USA)
6-Mitsubishi (Japan & USA)
7-Sumitomo-Titanium (Japan)
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