Back to supply chains
Where does Tongwei Solar source its components?
China. Supply chain mapped to 33 inputs across 6 countries.
Federal screeningFlagged
Yes. Tongwei Solar is organized in China, a covered nation under the FEOC rules, which makes it a foreign entity of concern for IRA clean-energy tax credit purposes. It is not named on any of the 3 federal restricted-party lists screened for this record (DOD Section 1260H, BIS Entity List, OFAC SDN List). Is Tongwei Solar a Foreign Entity of Concern?
Upstream sourcing exposure
High86% weighted
28 in covered nations - 1 elevated, of 33 nodes.
Where inputs are mined and refined. Not a FEOC determination for the company -- see the federal list screening above.
Refining chokepoint
5 of 5 processing/refining steps in covered nations
Producer1
Component12
Processing / Refining5
Raw Material6
Mine / Extraction8
Logistics1
designated covered nation elevated no known factor not assessed
Loading chain view...
Sourcing Concentration by Country
Covered NationAllied NationOther
Sourcing risk across the graph
Where each input is mined or refined. Not a FEOC determination for the company.
0
Designated (0%)
28
Covered nation (85%)
1
Elevated (3%)
4
No known factor (12%)
Legend
Node Types
Producer
Supplier
Component
Processing / Refining
Raw Material
Mine / Extraction
Logistics
Sourcing risk
Federally designated - named on a restricted-party list
Covered nation - sited in China, Russia, Iran or North Korea
Elevated - documented concentration risk, no federal listing
No known risk factor - not a compliance clearance
Not assessed - no sourcing judgement was made
Relationships
Transformation - manufactures / assembles
Refining - midstream processing (FEOC chokepoint)
Supply handoff - supplies / sources from
Arrows point in the direction material flows (input to product).
Every mapped input in the Tongwei Solar supply chain
33 nodes, grouped by supply-chain tier. Sourcing risk describes where an input is mined or refined; it is not a FEOC determination for Tongwei Solar.
Producer (1)
| Input | Origin | Sourcing risk | Basis |
|---|---|---|---|
| Tongwei Solar (TW Solar)Chengdu, Sichuan (HQ); cell/module plants Chengdu, Meishan, Hefei; Vietnam module line | China | Covered nation | World's largest polysilicon + solar cell maker; fully vertically integrated poly->wafer->cell->module. Chinese entity = FEOC-flagged. |
Component (12)
| Input | Origin | Sourcing risk | Basis |
|---|---|---|---|
| PV Module Assembly (N-type TOPCon)Chengdu / Hefei module lines; 90GW panel capacity | China | Covered nation | Final laminate: glass + encapsulant + cell string + backsheet + frame + junction box. Assembled in China. |
| Solar Cell (TOPCon)Meishan / Chengdu / Eshan; 150GW cell capacity | China | Covered nation | N-type Tunnel Oxide Passivated Contact cells, 22-23%+ efficiency. Made in-house by Tongwei. |
| Silicon WaferTongwei / partner ingot-wafer plants, China | China | Covered nation | Cz mono ingots grown from polysilicon, wire-sawn (~30% kerf loss). China controls ~97% of wafer output. |
| High-Purity Polysilicon (11N)Yongxiang: Leshan & Guangyuan (Sichuan), Baotou (Inner Mongolia), Baoshan/Baoshan Yunnan | China | Covered nation | 450-650kt/yr capacity, 99.999999999% purity via 8th-gen Yongxiang (modified Siemens) method. World #1. |
| Metallurgical / Industrial Silicon (MG-Si)Tongwei Green Substrate (Guangyuan) 200kt industrial silicon project; also sourced from Yunnan/Xinjiang smelters | China | Covered nation | Quartz reduced by carbon in submerged-arc furnace (~2000C). China makes ~70% of world MG-Si; Xinjiang a major hub (forced-labor risk). |
| Solar Glass (Low-Iron Tempered)Xinyi Solar / Flat Glass Group kilns, China (~76% of module mass is glass) | China | Covered nation | Low-iron ultra-clear front glass; Xinyi (~30% share) + FLAT dominate. China-made = flagged. |
| Silver Metallization PasteChinese paste makers (DuPont/Heraeus IP acquired by China entities) | China | Covered nation | Front/back busbar paste; ~1-2g Ag per panel. Cell metallization paste supply is now almost entirely China-based. |
| Aluminum FrameChinese extruders (anodized 6xxx alloy) | China | Covered nation | ~8% of module mass; stiffness/mounting. Extruded from Chinese primary aluminum = flagged. |
| EVA / POE Encapsulant FilmHangzhou First Applied Material (largest global encapsulant maker), China | China | Covered nation | POE preferred for N-type TOPCon (moisture/PID resistance). China-made = flagged. |
| Backsheet (PET / Fluoropolymer)Chinese backsheet laminators | China | Covered nation | PET core with PVDF (Kynar) or PVF (Tedlar) outer layer for weathering. China-laminated = flagged. |
| Copper Interconnect Ribbon (Tabbing/Busbar)Chinese ribbon makers | China | Covered nation | Oxygen-free copper coated with Sn-based solder alloy connects cells in series. China-made = flagged. |
| Junction Box + Bypass DiodesChinese J-box makers | China | Covered nation | Weatherproof enclosure housing bypass diodes and cable connectors. China-made = flagged. |
Processing and refining (5)
| Input | Origin | Sourcing risk | Basis |
|---|---|---|---|
| Quartz Beneficiation / Silica ProcessingChina silica processing plants | China | Covered nation | Crushing, washing, high-purity sorting of quartzite before smelting. China-processed = flagged. |
| Silver Refining (Doré -> 99.99% Ag)Chinese Ag refineries (byproduct of Pb/Zn smelting) | China | Covered nation | Silver powder for paste is refined largely in China; even allied-mined Ag refined in China = flagged. |
| Primary Aluminum Smelting (Hall-Heroult)Chinese aluminum smelters (Yunnan/Xinjiang/Inner Mongolia) | China | Covered nation | China smelts ~60% of world alumina/aluminum. Electrolytic reduction of alumina; China chokepoint = flagged. |
| Alumina Refining (Bayer Process)Chinese alumina refineries | China | Covered nation | Bauxite + caustic soda -> alumina. China = ~60% of global alumina. Refined in China = flagged. |
| Copper Refining (Cathode)Chinese copper smelters/refineries | China | Covered nation | China refines ~half of world copper cathode. Oxygen-free Cu for ribbon; China chokepoint = flagged. |
Raw material (6)
| Input | Origin | Sourcing risk | Basis |
|---|---|---|---|
| Trichlorosilane (TCS) PrecursorYongxiang chemical complexes, China | China | Covered nation | MG-Si + HCl -> TCS gas, then Siemens CVD decomposition onto hot rods yields solar-grade polysilicon. China-produced precursor. |
| Carbon Reductant (Coke / Coal / Woodchips)Chinese coal/coke supply (Xinjiang, Inner Mongolia) | China | Covered nation | Coke and low-ash coal reduce SiO2 in the arc furnace; ~10-12 MWh + carbon per ton Si. China coal-based = flagged. |
| Soda Ash (Sodium Carbonate)China soda-ash producers | China | Covered nation | ~254 kg soda ash per tonne PV glass as glass flux. China-sourced. |
| EVA / POE ResinPetrochemical crackers (China + imports) | China | Covered nation | Ethylene-vinyl-acetate / polyolefin elastomer resin; some high-grade POE resin still imported (Dow/Mitsui), converted in China. |
| Fluoropolymer (PVDF / PVF)Fluoropolymer producers (China + some US/EU imports) | China | Covered nation | PVDF/PVF weatherproof film; fluorspar-derived. Chinese fluoropolymer capacity growing; imports mixed. |
| Tin Solder AlloySn coating (China; Sn from China/Indonesia/Myanmar) | China | Covered nation | Sn-Pb or lead-free solder coat on ribbon. Tin supply partly Myanmar/Indonesia refined in China. |
Mine and extraction (8)
| Input | Origin | Sourcing risk | Basis |
|---|---|---|---|
| Quartz / Silica (Quartzite Ore)Vein-quartz mines, Xinjiang (~10% of China reserves) & other China deposits | China | Covered nation | SiO2 ore is the base feedstock for silicon metal. Xinjiang quartzite sourcing carries UFLPA/forced-labor exposure. |
| Ultra-Low-Iron Silica SandLow-iron quartz sand deposits, China (Fe2O3 < 0.012%) | China | Covered nation | ~745 kg quartz sand per tonne PV glass. Asia-Pacific = 46% of low-iron silica sand supply. |
| Silver Ore (Mexico)Zacatecas / Durango / Chihuahua mines | Mexico | No known risk factor | Mexico = world's #1 silver producer (~6,300 t, 2024). Mine allied; FEOC risk arises at China refining/paste step. |
| Silver Ore (Peru)Peruvian polymetallic mines | Peru | No known risk factor | Peru ~3,100 t (2024), largest reserves. Allied mine; flagged only if refined in China. |
| Silver Ore (China)Chinese Pb/Zn mines (silver byproduct) | China | Covered nation | China ~3,300 t (2024), mostly base-metal byproduct. China-mined = flagged. |
| Bauxite Ore (Guinea)Boke region bauxite mines, Guinea | Guinea | Elevated sourcing risk | Guinea = world's #1 bauxite (~130 Mt, 2024), heavily exported to China. Mine non-China but refining downstream is Chinese. |
| Bauxite Ore (Australia)Weipa / Gove bauxite mines, Australia | Australia | No known risk factor | Australia ~100 Mt (2024). Allied mine; flagged risk enters at Chinese alumina/aluminum refining. |
| Copper OreChilean copper mines (also Peru/DRC) | Chile | No known risk factor | Chile = top copper producer; allied mine. FEOC risk enters at Chinese refining. |
Logistics (1)
| Input | Origin | Sourcing risk | Basis |
|---|---|---|---|
| Module Export LogisticsShanghai / Ningbo ports; Vietnam re-export line | China | Covered nation | Modules shipped from Chinese ports; some finishing via Vietnam plant to navigate tariffs/UFLPA scrutiny. |
Material flow (32 relationships)
- Tongwei Solar (TW Solar) manufactures PV Module Assembly (N-type TOPCon) (PV module)
- PV Module Assembly (N-type TOPCon) assembles Solar Cell (TOPCon) (solar cell string)
- PV Module Assembly (N-type TOPCon) assembles Solar Glass (Low-Iron Tempered) (front glass)
- PV Module Assembly (N-type TOPCon) assembles EVA / POE Encapsulant Film (encapsulant film)
- PV Module Assembly (N-type TOPCon) assembles Backsheet (PET / Fluoropolymer) (backsheet)
- PV Module Assembly (N-type TOPCon) assembles Aluminum Frame (aluminum frame)
- PV Module Assembly (N-type TOPCon) assembles Junction Box + Bypass Diodes (junction box)
- PV Module Assembly (N-type TOPCon) assembles Copper Interconnect Ribbon (Tabbing/Busbar) (interconnect ribbon)
- PV Module Assembly (N-type TOPCon) supplies Module Export Logistics (finished module export)
- Solar Cell (TOPCon) assembles Silicon Wafer (silicon wafer)
- Solar Cell (TOPCon) assembles Silver Metallization Paste (silver metallization)
- Silicon Wafer refines High-Purity Polysilicon (11N) (polysilicon -> ingot -> wafer)
- High-Purity Polysilicon (11N) refines Trichlorosilane (TCS) Precursor (trichlorosilane precursor)
- Trichlorosilane (TCS) Precursor refines Metallurgical / Industrial Silicon (MG-Si) (metallurgical silicon -> TCS)
- Metallurgical / Industrial Silicon (MG-Si) sources from Quartz Beneficiation / Silica Processing (processed quartz feedstock)
- Metallurgical / Industrial Silicon (MG-Si) sources from Carbon Reductant (Coke / Coal / Woodchips) (carbon reductant)
- Quartz Beneficiation / Silica Processing refines Quartz / Silica (Quartzite Ore) (quartzite ore -> silica)
- Solar Glass (Low-Iron Tempered) sources from Ultra-Low-Iron Silica Sand (low-iron silica sand)
- Solar Glass (Low-Iron Tempered) sources from Soda Ash (Sodium Carbonate) (soda ash flux)
- Silver Metallization Paste sources from Silver Refining (Doré -> 99.99% Ag) (refined silver powder)
- Silver Refining (Doré -> 99.99% Ag) refines Silver Ore (Mexico) (silver ore -> refined Ag)
- Silver Refining (Doré -> 99.99% Ag) refines Silver Ore (Peru) (silver ore -> refined Ag)
- Silver Refining (Doré -> 99.99% Ag) refines Silver Ore (China) (silver ore -> refined Ag)
- Aluminum Frame sources from Primary Aluminum Smelting (Hall-Heroult) (primary aluminum billet)
- Primary Aluminum Smelting (Hall-Heroult) refines Alumina Refining (Bayer Process) (alumina -> aluminum)
- Alumina Refining (Bayer Process) refines Bauxite Ore (Guinea) (bauxite -> alumina)
- Alumina Refining (Bayer Process) refines Bauxite Ore (Australia) (bauxite -> alumina)
- EVA / POE Encapsulant Film sources from EVA / POE Resin (EVA/POE resin)
- Backsheet (PET / Fluoropolymer) sources from Fluoropolymer (PVDF / PVF) (PVDF/PVF film)
- Copper Interconnect Ribbon (Tabbing/Busbar) sources from Copper Refining (Cathode) (oxygen-free copper)
- Copper Interconnect Ribbon (Tabbing/Busbar) sources from Tin Solder Alloy (solder coating)
- Copper Refining (Cathode) refines Copper Ore (copper ore -> cathode)
Sources and methodology
Research-based supply-chain map compiled from public sources - not an audited bill of materials. Tiers reflect the standard industry structure for this product. Sourcing risk on a node describes where that input is typically mined or refined; it is not a FEOC determination for Tongwei Solar, and it is not a screening result for the node itself unless a federal listing is cited against it. Verify against primary documentation before making a compliance determination.
Primary sources (2) - government, filings, standards bodies
Secondary sources (27) - trade press, analysts, reference works
- en.wikipedia.org en.wikipedia.org/wiki/Tongwei_Company
- hssolar.com hssolar.com/news-59.html
- pv-tech.org pv-tech.org/tongwei-sets-sizeable-solar-polysilicon-cell-manufacturing-capacity-targets-following-q1-profit-leap/
- pv-magazine.com pv-magazine.com/2023/02/09/tongwei-adds-solar-modules-to-its-pv-powerhouse/
- en.tongwei.cn en.tongwei.cn/knowus.html
- bernreuter.com bernreuter.com/newsroom/press-releases/tongwei-dominates-the-polysilicon-industry/
- energytrend.com energytrend.com/news/20230329-31522.html
- itif.org itif.org/publications/2025/09/08/china-plans-to-dominate-a-key-semiconductor-material/
- responsiblesourcingtool.org responsiblesourcingtool.org/wp-content/uploads/2025/11/2025-Polysilicon-Commodity-Report-Final.pdf
- csri.global csri.global/launch-report/5-clean-energys-dirty-secret-how-can-solar-cut-its-dependence-on-xinjiang-forced-labour
- thebreakthrough.org thebreakthrough.org/issues/energy/sins-of-a-solar-empire
- scmp.com scmp.com/news/china/article/3153656/rare-form-quartz-key-xinjiangs-solar-boom-and-almost-all-it-us
- targray.com targray.com/solar/solar-frames
- emmveepv.com emmveepv.com/blogs/raw-materials-are-used-in-pv-solar-panel-manufacturing
- renewableenergyworld.com renewableenergyworld.com/solar/dupont-heraeus-roll/
- chemicalresearchinsight.com chemicalresearchinsight.com/2026/04/03/top-10-companies-in-the-hpbc-silver-paste-industry-2026-market-leaders-enabling-high-efficiency-solar/
- xinyisolar.com xinyisolar.com/en/SolarPvGlass/index.aspx
- dataintelo.com dataintelo.com/report/ultra-low-iron-silica-sand-for-solar-glass-market
- pubs.rsc.org pubs.rsc.org/en/content/articlehtml/2025/se/d4se01567c
- investingnews.com investingnews.com/daily/resource-investing/precious-metals-investing/silver-investing/top-silver-producing-countries/
- worldpopulationreview.com worldpopulationreview.com/country-rankings/silver-production-by-country
- investingnews.com investingnews.com/aluminum-production-by-country/
- elements.visualcapitalist.com elements.visualcapitalist.com/how-is-aluminum-made/
- valeoproducts.com valeoproducts.com/solar-panel-manufacturing-materials-a-complete-technical-guide/
- heavengreenenergy.com heavengreenenergy.com/glossary/fluoropolymer-backsheet
- cen.acs.org cen.acs.org/energy/solar-power/US-solar-polysilicon-supply-problem/100/i33
- viewpoint.bnpparibas-am.com viewpoint.bnpparibas-am.com/what-you-need-to-know-about-polysilicon-and-its-role-in-solar-modules/
Common questions
- Where does Tongwei Solar source the inputs in this product?
- This map traces 33 inputs across 6 countries, including 13 mines and refiners. It is compiled from public sources and is not an audited bill of materials.
- How much of the Tongwei Solar supply chain sits in a covered nation?
- 28 of 33 mapped inputs are sited in a covered nation (China, Russia, Iran or North Korea) or named on a federal restricted-party list. A further 1 carry elevated sourcing risk without either basis.
- Is Tongwei Solar itself a Foreign Entity of Concern?
- Yes. Tongwei Solar is organized in China, a covered nation under the FEOC rules, which makes it a foreign entity of concern for IRA clean-energy tax credit purposes. It is not named on any of the 3 federal restricted-party lists screened for this record (DOD Section 1260H, BIS Entity List, OFAC SDN List). Sourcing risk in this map describes where inputs are mined and refined and is a separate question from the company's own federal screening.