"I certainly hope not," the Premier said, hinting the province will increasingly rely on nuclear generation to avoid blackouts when a long-term energy plan is released in a few weeks.
McGuinty acknowledged the possibility of nuclear accidents is "an issue," but said Canadian reactors have not suffered a major problem like Chernobyl and labelled "irresponsible" opposition attempts to compare the systems.
"The fact is there's nothing available out there that doesn't have some kind of down side," he said, referring to other sources of electricity generation.
While problems with nuclear power include long-term waste storage, other less controversial forms of generation have disadvantages, including the rising price of natural gas, "visual pollution" of wind turbines and the high cost of solar energy, he said.
"There's nothing that's neat and tidy by way of a solution. So that's the reason we've got to keep nuclear on the table."
The comments come as Energy Minister Donna Cansfield prepares a reply to recommendations from the Ontario Power Authority on how to generate extra electricity needed to meet Ontario's fast-growing needs for a couple of decades.
The authority said in December the province should spend $40 billion to produce 12,400 megawatts of power from new or refurbished nuclear plants over the next 20 years.
Cansfield said government is looking at a "mix" of sources but insisted no final decisions have been made by cabinet, which must approve new electricity sources to replace coal-fired plants closing in a few years.
Officials were to announce the plan next week but that appears to have been derailed given Wednesday's anniversary of the explosion, which sent clouds of deadly radiation over much of Europe, killed at least 9,000 and left tens of thousands ill.
McGuinty denied the delay was prompted by the renewed focus on Chernobyl. "I wasn't aware of that," he said, saying the complexity of securing power supplies is the reason.
"Obviously, this is one heck of a big issue. We want to make sure that we get it right."
Critics said McGuinty is misleading the public in crediting Canadian reactors for solid safety records when incidents of concern include a major coolant leak at Pickering on Dec. 10, 1994. That's when 130 tonnes of radioactive heavy water gushed onto the plant floor, prompting an investigation by the International Atomic Energy Agency.
"These accidents can happen," said David Martin, energy co-ordinator at Greenpeace. He said the government has paid "lip service" to energy conservation and alternative sources of power in its rush to expand nuclear, predicting it could come back to haunt the Liberals in the 2007 provincial election. "Their timing's really bad."
The electricity issue has proved a hot potato for the McGuinty government, which originally promised to freeze hydro rates until 2006 but raised them shortly after being elected. Last week, they were raised by up to 16 per cent across the province, with Toronto households to pay an average of 5.8 per cent more a year starting May 1, as Ontario moves to charging residents the true cost of power. Rates had been subsized for years, running up a huge public debt.
High demand for power in recent years and a supply shortage has forced Ontario to import expensive electricity from neighbouring jurisdictions.
Hydro-Quebec CEO Thierry Vandal said yesterday the utility is considering boosting power exports to Ontario. "We think that there's room for growth for Hydro-Quebec in this market. It's a market that's of great interest for us," Vandal said after a speech to the Empire Club.
Hydro-Quebec, which made $220 million in sales in Ontario last year, will also lend as needed when electricity demand reaches peak levels in the summer