Polysilicon: Feedstocks
Why electricity, not silicon, is the real raw material
What this tab covers What it is made from and what it feeds: the raw materials and energy per tonne with their share of cost (linked to the commodity table), who is low-cost and why, and the chemicals made from it.Polysilicon is made from metallurgical silicon, hydrogen chloride and hydrogen, but electricity is the decisive input: 48-55 MWh per tonne by Siemens. That is why Chinese plants sit in Inner Mongolia, Xinjiang, Sichuan and Yunnan, where coal or hydro power is cheap.
Inputs per tonne
| Input | Quantity per tonne | Role | Share of cost | Source |
|---|---|---|---|---|
| Si Silicon | about 1.1 t per t polysilicon (indicative) | silicon source | silicon metal fell from RMB 15,000/t to RMB 8,500/t in 2024-25; about a quarter of cash cost (indicative) | China Polysilicon 2026 report; share indicative |
| Tc Thermal coal | 48-55 MWh (Siemens); 11-20 MWh (FBR) | reactor heating and conversion | largest single cash cost (indicative) | China Polysilicon 2026 report |
| NaCl Salt | make-up only; chlorine is recycled (indicative) | chlorosilane chemistry | small | Indicative |
| Hydrogen | make-up only (indicative) | reducing gas | small | Indicative |
| Steam and water | about 2.3 t steam and 8 t water (Siemens average) | utilities | small | China Polysilicon 2026 report |
Who is low-cost, and why
GCL's FBR (about RMB 25/kg cash) and Xinte's rods (about RMB 26/kg) are lowest; Tongwei and Daqo follow at RMB 30-35/kg. Wacker, OCI and Hemlock cost far more but sell into tariff-protected or semiconductor markets.