Polysilicon Proclamation: Understanding the Impacts to the Solar Supply Chain

On August 6, 2026, President Trump signed a presidential proclamation (link) imposing tariffs and minimum prices on imported polysilicon and its derivatives—including silicon wafers, solar cells, solar modules, and semiconductors—under Section 232 of the Trade Expansion Act of 1962. The action follows a Section 232 investigation initiated by the U.S. Department of Commerce on July 1, 2025, which examined U.S. dependence on foreign sources of polysilicon and the national security implications of concentrated overseas supply chains.