Cockatoo issued 40 million shares to KEPCO Australia and East-West Power (EWP) for $16.8 million cash.
EWP, a subsidiary of KEPCO, consumes 11.5 million tonnes of coal per annum, forecast to rise above 18.5Mt by 2016.
Government owned KEPCO generates 90% of Korea's power.
Cockatoo said the new capital will be used to expand the company's coal project portfolio and exploration and development programs.