Washington is weighing tariffs and a price floor on imported polycrystalline silicon, following a national-security investigation aimed at rebuilding the US supply chain for semiconductors and solar panels.
Washington has announced plans to impose tariffs on imports of polycrystalline silicon and its derivatives, a material essential to the manufacture of semiconductors and solar panels. Howard Lutnick, the Secretary of Commerce, presented the measure from the White House, with Donald Trump present. The announcement follows a series of efforts to relocate solar production to the United States, echoing recent investments in a one-gigawatt solar factory in California and in the Rockhound solar complex in Texas.
According to Howard Lutnick, the goal of the tariffs is to attract the upstream links of the polycrystalline silicon value chain to the United States. “We make the products here but we also need to bring the supply chain here. We’re putting tariffs in place to send a signal to build here. Our industry in this area is too limited,” he said. The US administration is also expected to introduce a price floor on imported polycrystalline silicon, a measure that would pursue the same objective as the tariffs: limiting the cost advantage held by foreign suppliers.
This dual approach — tariffs and a price floor — reflects the administration’s intent to support localized production against foreign competitors seen as too price-competitive. Polycrystalline silicon is an upstream input, processed into ingots and then wafers for photovoltaic cells, as well as into ultra-high-purity material for certain uses in the semiconductor industry. The US decision therefore targets not only the raw product but also derivatives integrated into more advanced components.
The US Department of Commerce opened an investigation on July 1, 2025, into imports of polycrystalline silicon and derivative products. The process relies on Section 232 of the Trade Expansion Act of 1962, a provision used when imports are deemed likely to affect US national security. According to the notice published in the Federal Register on July 16, 2025, the investigation examined the effects of these imports on national security and sought comments, data and analysis from interested parties.
The Bureau of Industry and Security, the Commerce Department agency responsible for controlling strategic exports, led this consultation phase. This legal framework authorizes the US president to adjust imports of a product—through tariffs, quotas or other restrictions—once the Secretary of Commerce concludes there is a threat to national security. The administrative case file for the investigation is identified under reference BIS-2025-0028, with a public comment period that closed on August 6, 2025.
Washington’s justification is rooted in a global solar supply chain that remains heavily concentrated. According to a 2026 publication by the Organisation for Economic Co-operation and Development, Chinese companies accounted for nearly 95% of global polysilicon production in 2025, while their share reached at least 80% across the main segments of the photovoltaic supply chain. This concentration fuels the US argument regarding industrial dependence on polysilicon for critical uses in chips and solar panels.
The US Department of Energy had already noted that the United States raised tariffs to 50% in 2024 on semiconductors, solar modules, cells, wafers and polysilicon, as part of earlier trade measures. The new measures on polycrystalline silicon would add to this already dense tariff framework surrounding solar and electronic equipment, as the US administration seeks to consolidate every link of the supply chain, from raw material to finished components.
President Donald Trump has signed a proclamation imposing an additional tariff and an import price floor on polysilicon, a key material for semiconductors and solar panels, set to
The reference media for the energy transition: markets, projects, regulation and jobs.

source