Australian coal-mining companies may lose more than 350 million Australian dollars, or $301 million, this year because bottlenecks and storms are delaying ships outside Newcastle, the world’s largest port for coal exports.

Xstrata, the world’s biggest thermal coal exporter, estimates that miners in New South Wales’s Hunter Valley are paying about 1 million dollars a day in penalties for idling ships, said an Xstrata spokesman, James Rickards. The delays are expected to cost 460 million dollars in 2007, Australia’s competition regulator said in March.

Coal prices jumped to a record above $70 a metric ton in the week ended June 29, and freight rates are near all-time highs. Storms last month drove a ship ashore and disrupted Newcastle loadings for two weeks, worsening delays due to inadequate rail and terminal capacity. About 8 percent of the bulk shipping fleet is anchored off Brazil, China and Australia.

“Most of the vessels are tied up in Australia,” Nicolai Hansteen, an analyst at the Oslo-based shipbroker Lorentzen & Stemoco, said in a phone interview. “Definitely, the port congestion situation will continue to be a major factor over the next three to five years.”

The line of ships waiting to load coal at Newcastle stretched to a record 79 on June 2, and shortened to 69 as of Monday. Bottlenecks are costing miners like Xstrata, BHP Billiton and Rio Tinto Group about 2 billion dollars in lost sales from Australia, said the Queensland Resources Council, which represents mining companies.

The nation shipped coal worth 20.4 billion dollars in the year ended May, or 12.9 percent of the country’s total exports, the single largest component, according to government statistics.

Coal & Allied Industries, an Australian thermal coal producer controlled by Rio Tinto, posted a 63 percent fall in second-half profit because of port delays and warned that this year’s financial performance would be “substantially adversely affected” by the bottlenecks. Rio Tinto’s spokeswoman, Alison Smith, did not respond to e-mailed questions.

The Australian Competition and Consumer Commission in May recommended reinstating coal export quotas at Newcastle to reduce delays.

“There are no quick fixes,” said Xstrata’s Rickards. “It’s important for producers in the Hunter Valley region to work together not only for port facilities but also rail.”

BHP is part of the Newcastle Coal Infrastructure Group, which is studying coal growth options in the Hunter Valley. The New South Wales government has approved the group’s application to build and operate a third coal export terminal in Newcastle.

Almost 10 percent of the world’s Capesize vessels, the largest of bulk carriers, and about 5 percent of the Panamax fleet, vessels able to carry about 75,000 tons of cargo, are tied up in Australian ports, Pareto Bassoe Shipbrokers Group said in May.

Delays in Australia have forced Asian coal buyers to seek alternative supplies from Indonesia and South Africa. China’s switch this year to net imports, to power the world’s fastest-growing major economy, is increasing coal’s scarcity and adding urgency to plans to improve Australia’s infrastructure.

“We are diversifying our sources, especially, when there are shortages and it becomes feasible, we buy coal from South Africa,” which is more expensive than in Australia or Indonesia, said Sou Yoshinaga, a spokesman for Japan’s Electric Power Development, Asia’s second-biggest buyer of thermal coal.

Vessels were waiting more than 32 days on average to load coal, compared with 18 hours for general cargo, Newcastle Port said. The port accounts for a third of Australian exports of the fuel used for power generation. Ships are also lined up at Dalrymple Bay and Gladstone, Australia’s next-largest coal terminals.

The delays are driving up shipping rates, adding to the record $70.88 a metric ton price paid by Asian utilities for coal at Newcastle for the week ended June 29, according to the globalCOAL NEWC index. The price had fallen to $67.56 as of last Friday.

The Baltic Dry Index, or BDI, a measure of the costs of hiring ships to carry coal, iron ore and other so-called dry-bulk commodities, has jumped 40.3 percent this year, as delays keep ships from loading.

Japan buys 60 percent of its coal from Australia, and delays threaten the energy security of Asia’s largest economy, said Atsuo Sagawa, a senior coal market researcher at the Institute of Energy Economics, Japan.

Power utilities should be able to manage temporary supply shortages because they have stockpiles equivalent to about 45 days of consumption, Sagawa said. “But if supply disruptions from Australia persist for longer, it could develop into a serious concern,” he said.