Stephen Harper is often accused of being absent on environmental issues, but in a year-end interview with CBC News chief correspondent Peter Mansbridge, the prime minister said his government is doing its bit to combat climate change and that greenhouse gas emissions have dropped on his watch.

"We’ve got more work to do, but our emissions are falling," Harper said on Wednesday.

"Other countries’ emissions for the most part are going up. World emissions are going up. Canada’s have not been going up."

Canada's emissions have dropped since 2008 largely because of the recession and industry slowdown. They have remained flat since 2010.

But the government's own report suggests emissions will go up dramatically by the end of the decade because of oil and gas production, Canada's emissions will be 22 per cent higher than its Copenhagen target of reducing greenhouse gases by 17 per cent below their 2005 levels by 2020.

The prime minister has resisted imposing federal rules on the oil and gas industry unless the U.S. does too.

Last week, he called the idea "crazy."

"Under the current circumstances of the oil and gas sector, it would be crazy, it would be crazy economic policy to do unilateral penalties on that sector. We're clearly not going to do it," Harper said in the House of Commons.

Carbon-pricing convert?

Now Harper says he'd be open to using a carbon-pricing system like Alberta's for the entire continent, a concept he's previously opposed.

"I think it’s a model on which you could, on which you could go broader," Harper said in Wednesday's interview.

"It's not a levy, it's a price. And there's a tech fund in which … [the] private sector makes investments."

Alberta requires big companies to reduce their energy intensity, in other words improve their energy efficiency, annually. If they don't, they pay into technology fund at $15 a tonne for carbon emissions.

David McLaughlin, an adviser at the University of Waterloo’s school of environment, says emissions continue to rise under Alberta's system of carbon pricing.

"The price of $15 a tonne is too low to actually get the emissions reductions we want from these big emitters. So it would not do the job of reducing emissions in Canada."

The prime minister also took credit for getting tough on coal.

"We are phasing out in Canada through regulations, we are phasing out the use of traditional dirty coal. It’s going to go to zero in the next 15 years or so," Harper said.

New federal coal regulations apply to new plants built after 2015. Existing plants built in the last 50 years are grandfathered, meaning they would have up to 2030 to close or introduce carbon capture and storage technology to reduce emissions.

Ontario's Environment Minister Glen Murray points out the province closed coal plants with no help from Ottawa.

"if the federal government wants to start taking credit for provincially funded initiatives, they could at least have the decency to make a commitment to support those initiatives in the future."

Harper's comments could be more about politics than policy — an attempt to soften his image on the environment in an election year when climate change is again becoming a hot political topic.