Trump Polysilicon Tariff Sets 15% Duty, Price Floors on Imports

(Bloomberg) – President Donald Trump ordered a 15% tariff on imported polysilicon and polysilicon derivatives including silicon wafers and solar modules, alongside minimum import prices, in a bid to rebuild domestic production capacity. The proclamation, signed Thursday, takes effect Dec. 4.

The measure sets floor prices: $21 per kilogram for polysilicon, $100 per kilogram for ingots and wafers, 22 cents per watt for solar cells and 38 cents per watt for solar modules. The action is meant to encourage US manufacturing of polysilicon and goods made from it, supporting a solar supply chain that has struggled to take root for more than a decade.

Shares of US solar manufacturers with domestic operations jumped in after-hours trading. First Solar Inc., the country's biggest solar maker, climbed as much as 8%. T1 Energy Inc. rose 6.3%.

The new import fees threaten to raise the cost of solar modules, adding pressure on renewable developers already bracing for the loss of federal subsidies and a presidential administration that favors fossil fuels.

The order includes an incentive program. The Commerce secretary can enter into company-specific deals to encourage US production. Companies that submit approved onshoring plans can import some equipment and inputs duty-free. The administration said it will police stockpiling: any firm found building inventory of duty-free polysilicon before Dec. 4 faces import restrictions.

Manufacturing groups praised the move. Jon Toomey, president of the Coalition for a Prosperous America, called it the first time the US has protected the entire solar supply chain with a single action.

"For the first time, the United States is protecting the entire solar supply chain with a single action – and rewarding the manufacturers that build here – while taking a significant step to bolster the domestic semiconductor supply chain. This is how you reshore an industry," Toomey said.

The delayed start gives importers nearly two months to front-load purchases before the tariff takes effect. Trump's order says the administration will monitor for stockpiling and restrict imports from companies found building inventory.

The tariff follows years of US trade cases that layered duties on solar equipment from China and some Southeast Asian nations. Foreign manufacturers shifted production between countries to evade tariffs, making enforcement difficult. Trump's new measure attempts to close that gap with a single broad action.

The US was a leading polysilicon producer in the early 2000s. Chinese companies rose to dominance and by the end of the 2010s controlled most of the global supply. Antidumping and countervailing duties since then have targeted Chinese imports and transshipment routes through Southeast Asia.

For solar developers, the added import costs compound existing pressure from fading federal tax credits and a policy tilt toward oil and gas. The price floors could push module prices higher, squeezing project margins.

First Solar, which scores a Mixed 55 on AlphaScala's proprietary metric, rose 8% in after-hours trading. FSLR stock page

The tariff takes effect Dec. 4. Developers face a two-month window to import duty-free equipment before the new costs hit.