Unfavorable exchange rates and the impacts on the logistics chain from a ship loader outage at the Newcastle port also contributed to first quarter seaborne thermal segment costs rising to US$36 per short ton - 14% higher than the prior year.
Those impacts were partially offset by cost improvements at Peabody's Wilpinjong mine in NSW.
The thermal segment reported adjusted earnings before interest, tax, depreciation and amortisation of $28.5 million.
In the first quarter, Wilpinjong sold 2.9Mt at a cost of $23/t and contributed approximately $24.6 million to the seaborne thermal segment's adjusted EBITDA.
Wilpinjong had $6.1 million of capital expenditures in the first quarter.
Turning to the seaborne met coal segment, the company shipped 1Mt, including 100,000t from idled operations, at an average realised price of $87/t in the first quarter.
Seaborne met costs, excluding idled operations, were approximately $84/t.
Total segment costs of $110/t were in line with the prior year. Productivity improvements at its Moorvale mine in Queensland offset the impacts of unfavorable exchange rates and idled mine costs at Metropolitan in NSW.
The met coal segment reported an adjusted EBITDA loss of $22.4 million.
Peabody CEO Glenn Kellow said the company continued to implement operational and productivity improvements.
"Looking ahead, we remain focused on further improving our seaborne metallurgical cost structure and capturing continued cash improvements across the organisation while positioning for ongoing seaborne market improvements," he said.
Peabody said prices for Australian hard coking coal continues to be impacted by the China ban on Australian coal, in addition to increased COVID-19 concerns in India.
"Prices for low-vol pulverised coal injection coal are at parity with Australian hard coking coal as tight supply and China paying premiums for Russian coals have resulted in higher prices," it said.
Peabody anticipates volumes and costs for its seaborne thermal segment will progressively improve throughout the year as the company's mines continued to safely operate throughout the quarter.
For the full year, seaborne thermal volumes are expected to be approximately 17Mt, including 7-8Mt.
Seaborne thermal costs per ton are expected to increase compared to 2020 levels given lower volumes, higher expected royalties and unfavorable exchange rates.