Since replacing former premier Dalton McGuinty in January, Wynne has maintained she was willing to appear before the opposition-dominated committee, and would release all the relevant documents on the cancelled energy projects.
"I really believe that it's very important that I am the premier who has asked the auditor general to look at those costs to make sure that the calculations made are open and transparent," she told the legislature.
"That's why we asked the auditor general to look at it."
Wynne defended the government's decision to cancel the two gas plants, which were opposed by local residents in both communities, and noted the Tories and NDP agreed the projects should be moved elsewhere.
"We made the decision to relocate those gas plants, and there were costs associated with that," she said.
The auditor reported last week that the cost of scrapping the Mississauga gas plant in mid-construction, just days before the 2011 election, was $275 million, not the $190 million the Liberals had been claiming.
The auditor is also investigating the 2010 cancellation of an even larger gas plant planned in Oakville, which the government says cost $40 million, but the report into that project isn't expected until August.
Last week, Wynne insisted it would be wrong for the government to provide an updated cost for the Oakville plant before the auditor completes his investigation.
But the Liberals said Tuesday they wanted the committee to hear from Colin Andersen, the CEO of the Ontario Power Authority, who the government said could provide updated costs on the Oakville cancellation.
"The OPA will be in a position to share their current estimate of long-term costs and savings associated with the relocation of the Oakville plant," said Chiarelli.
However, the opposition parties blocked Anderson's testimony until next week, which the Liberals complained would prevent the planned appearance of Progressive Conservative Leader Tim Hudak before the committee.
Hudak had also made a campaign promise to scrap the unpopular Mississauga gas plant, and the government wants to know what the Tories thought the cancellation would cost taxpayers.
"They were the ones opposed to the gas plants, but when we cancelled them they cried foul," said government house leader John Milloy.
"If it’s such an important issue, we’d like to know what their figures were and we look forward to Mr. Hudak coming."
The Progressive Conservatives and New Democrats estimate the cost of cancelling the Oakville gas plant will be closer to $1 billion.
Meanwhile, former energy minister Chris Bentley testified Tuesday that he initially blocked the release of some gas plant documents because making them public would have hurt the province's negotiating position and cost taxpayers more in the long run.
"I was attempting to the best of my ability to reconcile two very important principles: protecting the financial interests of the people of Ontario, which I honestly believed were at risk, and the right of members to ask for what they want in the course of a committee proceeding," said Bentley.
"The whole proceeding has been very, very challenging and very difficult."
Bentley was the target of a contempt of parliament motion last fall over the gas plant documents, and resigned from government in February after Wynne won the Liberal leadership.
Bentley stuck to the $40 million price for cancelling the Oakville plant, but admitted the OPA was on the hook for other costs including $210 million for gas turbines purchased for the project.
Bentley's predecessor as energy minister, Brad Duguid, testified Tuesday that he recommended against scrapping the Mississauga plant, but got a call from the Liberal campaign team informing him they had decided not to go ahead with the project.
"I wasn't privy to the discussions around it with the (Liberal) party, but in the last days of the campaign I got a phone call which indicated they decided to cancel the plant," said Duguid.
The premier's office was clearly working around Duguid as energy minister when it came to the gas plants, said New Democrat Peter Tabuns.
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