Unlike the 2008 global economic downturn when prices rebounded "relatively quickly," the current downturn "could be significantly prolonged" eroding the full-year profit and denting earnings in the first half of 2013, he said.
The company won't pay an interim dividend, having paid the government $30 million at September 30 last year.
The kiwi dollar's strength against the greenback wiped about $12 million from earnings before interest and tax, it said. Exploration costs rose by $4.9 million to $15.7 million as the company ramped up exploration on the West Coast
"While the short-term economic environment will continue to drive volatility in international coal markets, we remain confident in our long-term outlook which is strong and unchanged," Palmer said.
Solid Energy, which is on the government's list for partial sale, is forecast to lift sales to $1.16 billion and profit to $170.9 million by 2016 with a growing but still minor contribution from wood pellets, biodiesel and briquettes, according to an assessment by brokerage Forsyth Barr. While sales would gain 96 per cent by 2016, coal production costs are forecast to grow a more sedate 36 per cent.
Production at Stockton Mine rose 8 per cent to 871,000 tonnes in the first half, while at Spring Creek output fell 28 per cent to 200,000 tonnes because the mine is being prepared for its next five-year extraction block.
Huntly East Mine's output fell 14 per cent to 169,000 tonnes, which the company said reflected harder mining conditions in some blocks. Rotowaro Mine output fell 6 per cent to 577,000 tonnes while at New Vale Mine in Southland, production rose 10 per cent to 156,000 tonnes.
Production overall has been hampered by a 20 per cent turnover rate for employees and Solid Energy is increasing its intake of bonded trainees, it said.
Wood pellet production rose 14 per cent to 25,000 tonnes while biodiesel output rose 27 per cent to 989,000 litres.