Hydro One makes its debut on the Toronto Stock Exchange today in one of the largest initial public offerings in Canada in 15 years.

The sale of just over 81 million shares, priced at $20.50 each, is the first step in the Ontario government’s plan to gradually part ways with 60 per cent of the giant transmission utility whose sale has sparked political controversy.

Three more offerings are expected to follow, with hopes of generating a total profit of $9 billion.

More than half of that will go to pay down hydro debt, while the rest will support infrastructure projects.