Ontario Power Generation will close four coal-burning power-generating units in 2010, provincial Energy Minister George Smitherman says.

OPG will close two of eight coal-burning units at its Nanticoke station near Simcoe and two of four units at its Lambton plant near Sarnia by October 2010, Smitherman said at a news conference in Toronto on Thursday.

The utility also closed Toronto's Lakeview Generating Station in 2005. Once the next four units are taken off-line, Ontario will have reduced its coal-burning capacity by 40 per cent.

Smitherman said the move would save lives by reducing air pollution and make more room for green, renewable forms of energy on the grid.

The provincial government said the latest scheduled closures would be four years ahead of the 2014 target to permanently shut down all of Ontario's coal-fired stations.

However, Dalton McGuinty's Liberal government had originally promised Ontario would stop burning coal to generate electricity by 2007, and had to push that deadline back more than once, to 2014.