Special minister of state John Della Bosca said on Friday that the federal and Victorian governments would retain the remaining 42% interest in the company.
He also said the government expects the public share sale to be completed by April next year, for a June listing.
Snowy Hydro owns a 3,756-megawatt hydroelectric power generating system in southeastern Australia, a power retailing business in Victoria and the Valley Power gas-fired generator in Victoria. It is also building another gas-fired power plant at Laverton, Victoria.
In recent years, the firm has invested almost A$500 million buying power assets in Victoria and South Australia, and on building new plants, the government said.
Snowy Hydro's plants, which run during high-demand periods, met about 5% of total energy demand in southeastern Australia.
In October, the National Electricity Market said summer maximum electricity demand in NSW was forecast to grow 3.9% a year over the next 10 years.