BILLINGS, Montana: A Navajo tribe-owned company has made the lowest offer seen in years for federal coal reserves, bidding less than a penny per ton in what became the largest U.S. coal sale in more than a decade.

Navajo Transitional Energy Co. (NTEC) offered US$186,000 to lease 167 million tons of coal on federal lands in southeastern Montana, the equivalent of one-tenth of a penny per ton. The offer highlights coal's sharply declining market value, even as President Donald Trump continues to push for expanded mining of the heavily polluting fuel.

Federal officials did not immediately say whether they would accept the bid, which was the only one received. Two NTEC representatives attended the sale at the Bureau of Land Management office in Billings, Montana, but declined to comment afterward.

The last successful federal coal lease in the region was more than a decade ago, when a Peabody Energy subsidiary paid $793 million or $1.10 per ton for 721 million tons of coal in Wyoming.

It remains unclear how much demand there will be for the coal offered on October 6, located next to NTEC's Spring Creek Mine near Decker, Montana. According to an Associated Press analysis, the five power plants currently using coal from that mine are scheduled to stop burning the fuel within the next decade.

The lease area lies within the Powder River Basin, the nation's most productive coal region. Leasing there was suspended under former President Joe Biden's administration because of coal's climate impact, but Republicans are now moving to reverse that policy.

In its filings, NTEC cited federal projections showing coal demand would continue to shrink over the next 20 years, justifying its low valuation of the lease area. The company bid $147 per acre for 1,262 acres (510 hectares) of land.

A separate lease sale is set for October 8 in central Wyoming, where the government will offer 440 million tons of coal next to NTEC's Antelope Mine.

The Trump administration allowed these sales to proceed despite the ongoing government shutdown, choosing not to furlough staff reviewing fossil fuel projects.

Many coal-fired power plants have closed in recent decades as utilities turn to natural gas and renewable sources like wind and solar.

Selling new leases does not guarantee the coal will ever be mined, said James Stock, a Harvard University economist and former member of the White House Council of Economic Advisers under President Barack Obama.

"Despite Trump's declaration of an energy ‘emergency' and his calls to expand mining and burning of coal, I don't expect these leases to have much real-world impact," Stock said. "It's unlikely any new coal plants will be built."

NTEC's Spring Creek mine also exports coal to Asian markets, which could help offset domestic declines. However, industry efforts to ramp up exports have been limited by a shortage of U.S. port capacity.