TORONTO -- Ontario's official opposition says the governors of New York, Pennsylvania and Ohio should send Premier Kathleen Wynne thank-you notes for the cheap power they're getting from the province.

Progressive Conservative Leader Patrick Brown says the province sold $9.4 million worth of excess electricity for just $144,000 on Nov. 10, which he suspects is a "record day for this government in terms of wasted power."

Brown says Ontario has "given away" $6 billion in surplus electricity since 2009 by selling it at a big loss, and claims that means businesses in the province have been subsidizing their competitors' power bills.

Energy Minister Glenn Thibeault admits the figures are shocking at first blush, but says Ontario made $230 million in 2015 by selling excess electricity to neighbouring jurisdictions.

Thibeault says Ontario suffered through power shortages and brown outs when the Conservatives were last in power, and had to spend up to $500 million a year to buy electricity from its neighbours to keep the lights on.

But Brown says Thibeault is being disingenuous because he knows it cost the province $9.4 million to produce the power it sold for $144,000 on Nov. 10.

"So it's a massive net loss, and I use that day because it was particularly suggestive of where we are," said Brown. "Only in Kathleen Wynne's world is that a good deal for Ontario."