Sweeping tariffs on imported aluminum imposed by U.S. President Donald Trump are succeeding in reshaping global trade flows and inflating costs for American consumers, but are falling short of their primary goal: to revive domestic aluminum production.

Instead, rising costs, particularly skyrocketing electricity prices in the U.S. relative to global competitors, are leading to smelter closures rather than restarts.

The impact of aluminum tariffs at 25% is starkly visible in the physical aluminum market. While benchmark aluminum prices on the London Metal Exchange provide a global reference, the actual cost of acquiring the metal involves regional delivery premiums.

This premium now largely reflects the tariff cost itself.

In stark contrast, European premiums were noted by JPMorgan analysts as being over 30% lower year-to-date, creating a significant divergence driven directly by U.S. trade policy.

This cost will ultimately be borne by downstream users, according to Trond Olaf Christophersen, the chief financial officer of Norway-based Hydro, one of the world’s largest aluminum producers. The company was formerly known as Norsk Hydro.

“It’s very likely that this will end up as higher prices for U.S. consumers,” Christophersen told CNBC, noting the tariff cost is a “pass-through.” Shares of Hydro have collapsed by around 17% since tariffs were imposed.

The downstream impact of the tariffs is already being felt by Thule Group, a Hydro customer that makes cargo boxes fitted atop cars. The company said it’ll raise prices by about 10% even though it manufactures the majority of the goods sold in the U.S locally, as prices of raw materials, such as steel and aluminum, have shot up.

But while tariffs are effectively leading to prices rise in the U.S., they haven’t spurred a revival in domestic smelting, the energy-intensive process of producing primary aluminum.

The primary barrier remains the lack of access to competitively priced, long-term power, according to the industry.

“Energy costs are a significant factor in the overall production cost of a smelter,” said Ami Shivkar, principal analyst of aluminum markets at analytics firm Wood Mackenzie.  “High energy costs plague the US aluminium industry, forcing cutbacks and closures.”

“Canadian, Norwegian, and Middle Eastern aluminium smelters typically secure long-term energy contracts or operate captive power generation facilities. US smelter capacity, however, largely relies on short-term power contracts, placing it at a disadvantage,” Shivkar added, noting that energy costs for U.S. aluminum smelters were about $550 per tonne compared to $290 per tonne for Canadian smelters.

Recent events involving major U.S. producers underscore this power vulnerability.

In March 2023, Alcoa Corp announced the permanent closure of its 279,000 metric ton Intalco smelter, which had been idle since 2020. Alcoa said that the facility “cannot be competitive for the long-term,” partly because it “lacks access to competitively priced power.”

Similarly, in June 2022, Century Aluminum, the largest U.S. primary aluminum producer, was forced to temporarily idle its massive Hawesville, Kentucky smelter – North America’s largest producer of military-grade aluminum – citing a “direct result of skyrocketing energy costs.”

Century stated the power cost required to run the facility had “more than tripled the historical average in a very short period,” necessitating a curtailment expected to last nine to twelve months until prices normalized.

The industry has also not had a respite as demand for electricity from non-industrial sources has risen in recent years.

Hydro’s Christophersen pointed to the artificial intelligence boom and the proliferation of data centers as new competitors for power. He suggested that new energy production capacity in the U.S., from nuclear, wind or solar, is being rapidly consumed by the tech sector.

“The tech sector, they have a much higher ability to pay than the aluminium industry,” he said, noting the high double-digit margins of the tech sector compared to the often low single-digit margins at aluminum producers. Hydro reported an 8.3% profit margin in the first quarter of 2025, an increase from the 3.5% it reported for the previous quarter, according to Factset data.

“Our view, and for us to build a smelter [in the U.S.], we would need cheap power. We don’t see the possibility in the current market to get that,” the CFO added. “The lack of competitive power is the reason why we don’t think that would be interesting for us.”

While failing to ignite domestic primary production, the tariffs are undeniably causing what Christophersen termed a “reshuffling of trade flows.”

When U.S. market access becomes more costly or restricted, metal flows to other destinations.

Christophersen described a brief period when exceptionally high U.S. tariffs on Canadian aluminum — 25% additional tariffs on top of the aluminum-specific tariffs — made exporting to Europe temporarily more attractive for Canadian producers. Consequently, more European metals would have made their way into the U.S. market to make up for the demand gap vacated by Canadian aluminum.

The price impact has even extended to domestic scrap metal prices, which have adjusted upwards in line with the tariff-inflated Midwest premium.

Hydro, also the world’s largest aluminum extruder, utilizes both domestic scrap and imported Canadian primary metal in its U.S. operations. The company makes products such as window frames and facades in the country through extrusion, which is the process of pushing aluminum through a die to create a specific shape.

“We are buying U.S. scrap [aluminium]. A local raw material. But still, the scrap prices now include, indirectly, the tariff cost,” Christophersen explained. “We pay the tariff cost in reality, because the scrap price adjusts to the Midwest premium.”

“We are paying the tariff cost, but we quickly pass it on, so it’s exactly the same [for us],” he added.

RBC Capital Markets analysts confirmed this pass-through mechanism for Hydro’s extrusions business, saying “typically higher LME prices and premiums will be passed onto the customer.”

This pass-through has occurred amid broader market headwinds, particularly downstream among Hydro’s customers.

RBC highlighted the “weak spot remains the extrusion divisions” in Hydro’s recent results and noted a guidance downgrade, reflecting sluggish demand in sectors like building and construction.

— CNBC’s Greg Kennedy contributed reporting.