New Hope Corp on Wednesday said that it is putting itself up for sale after being approached by several suitors, sending the Australian thermal coal miner's market value up by 15 per cent to nearly A$5.1 billion ($4.8 billion).

New Hope, Australia's second-largest listed coal miner by output, said that it will conduct a formal process and invite selected parties to submit bids, which may or may not result in a proposal being made or recommended by the board.

The Brisbane-based company did not reveal how many offers it had received but did say that the potential buyers were both local and overseas companies.

New Hope, which has A$1.5 billion in cash on its balance sheet and reported net income of $503.1 million last year, is an independent, energy company having open cut mines at Acland on the Darling Downs and at Rosewood near Ipswich.

The company focuses on niche marketing of its thermal coal and exports around 65 per cent of its coal production to Asia Pacific markets including Japan, Korea and Chile and the remaining to customers in south-east Queensland.

The company also holds various exploration tenements in central and southern Queensland.  New Hope also holds a 100-per cent shareholding a coal export terminal at the Port of Brisbane with capacity of 10 million mt/year, and significant land holdings around Ipswich and near its mining operations at Acland.

New Hope currently produces 6 million tonnes of thermal coal a year with plans to increase output to 12-15 million tonnes in the next five years.

The company's large shareholders are Australian investment company Washington H Soul Pattinson, which holds 59.71 per cent and Tokyo-based Mitsubishi Materials Corp with 11 per cent.

New Hope is more attractive than the recent coal assets acquisitions made by Indian companies in Australia because New Hope has its own infrastructure like port, and other handling facilities that make it easier to export to lucrative markets like China and India.

Potential suitors for New Hope could be Chinese and Indian companies as well as mining giants like Anglo Australian miners BHP Billiton and Rio Tinto, Swiss miner Xstrata, London-listed diversified mining company Anglo American, Vale of Brazil and Japanese power producers.

Buoyed by the strong yen and call for ending reliance on nuclear energy in wake of the explosions and radiation leak from the Fukushima plant due to the tsunami in March, Japanese companies are likely to bid for any thermal coal assets globally.

The most likely contenders are Xstrata and US coal mining giant Peabody, both of whom have their mines in close proximity to New Hope's Acland mine.

Indian coal miners have recently acquired several coal assets in Australia's remote Galilee Basin, but the infrastructure like rail and ports to export will take several years to develop.

A single Indian company may not have the resources to make such a large acquisition, but a consortium of state and private power producers can muster the A$5.1 billion to bag New Hope.