There's nothing wrong with public utilities donating money to the Ontario Liberal Party, Energy Minister Brad Duguid said Monday after the NDP charged the donations are driving up hydro bills.

The New Democrats released Elections Ontario documents showing that local utilities, including Newmarket-Tay Power and Oakville Hydro, donated thousands of dollars to the Liberal party in the past few years.

"Essex Power put nearly $3,000 into Liberal party coffers, while Thunder Bay Hydro made a donation to the Thunder Bay Superior North Liberal Riding Association," NDP Leader Andrea Horwath told the legislature.

"Why are families who are already feeling the squeeze funding the Ontario Liberal Party when they're paying their hydro bills?"

Duguid repeatedly refused to answer Horwath's questions in the legislature, and outside the chamber defended the political donations by utilities.

"We have the most stringent rules probably ever in Ontario in place and they apply to all three political parties," Duguid said.

"Those that make donations to the governing party make donations to the opposition generally as well."

Duguid wouldn't say whether he thought it was appropriate for municipally owned utilities to donate to political parties at a time when electricity rates are rising. Instead he repeated his statements about the donations following the rules.

Tories don't support NDP

The Progressive Conservatives also refused to support the NDP's call to change the rules to prohibit local utility companies from making political donations.

"I wouldn't advocate changing a system that is clear and transparent about where campaign contributions come from," Opposition Leader Tim Hudak said.

Each of the utilities named by the New Democrats said they never donated money directly to the Liberals, but rather purchased tickets to party fundraisers so they could network with cabinet ministers and industry officials on the Green Energy Act.

The Elections Ontario documents show Oakville Hydro gave the Liberals $8,500 in 2009 and another $7,000 in 2008.

Newmarket-Tay Power Corp. gave the Liberals $2,350 in 2009, but the money was used to buy tickets to fundraisers or for speeches by then energy minister George Smitherman, said CFO Ian Clinton.

"We would never make donations to a byelection," Clinton said. "We're a publicly funded utility company."

Ratepayer money not used: Oakville Hydro

Oakville Hydro did not use money from electricity ratepayers to buy tickets to Liberal fundraisers, but instead used funds from its other businesses, which included telecommunications and construction companies, CEO Bob Lister said.

"This would have been paid for by funds earned elsewhere than the electricity distributor," Lister said.

"From our perspective, it was an industry networking event to support the business needs of the corporation."

Essex Power Corporation donated $2,940 to the governing Liberals, $1,700 of which the party directed to the Toronto-Centre byelection, which the Liberals won in February this year.

The utility viewed the Liberal fundraisers as necessary networking events, Essex Power CEO Ray Tracey said.

"It's really to understand the direction of the government and... ensuring that if we're going to be making investments, we can be sure that there's a commitment to these [green energy] programs," Tracey said.

Other funds donated by the utilities were directed by the Liberals to last year's byelection in Haliburton–Kawartha Lakes–Brock, which the government won, defeating then PC leader John Tory.

"It's obvious that byelections provide that extra opportunity for more money to flow," Horwath said.

Other public utilities donating to the Liberals included Thunder Bay Hydro ($330), Greater Sudbury Hydro Plus ($520), St. Catharines Power Generation ($228) and Niagara-on-the-Lake Hydro ($215).

The government's refusal to change the rules or acknowledge that the political donations are inappropriate is a "slap in the face to every hydro ratepayer in this province," Horwath added.

"It is indefensible," she said. "There's no way that these public utilities should be donating to political parties. They benefit from it, [so] they don't want to change the rule."

The government pointed out that the NDP has also accepted donations from the energy sector, including $1,200 from Five Nations Energy Inc., which is jointly owned by the Attawapiskat, Kashechewan and Fort Albany First Nations.