It's generally accepted that a carbon tax is an efficient way of letting players in the economy determine the best way for them individually—as individuals or corporations—to reduce their emissions.
However, we estimated a couple of years ago that as a country, if we were to rely solely on a carbon tax to reduce our emissions to meet the Paris targets, or even exceed them, the carbon tax would need to be increased significantly and get close to $300 per tonne, as opposed to the maximum of $170 per tonne that it's scheduled to reach in 2030.
There would be quite a bit of further increases necessary to reach our targets as a country. While the literature suggests that a carbon tax is very efficient, I don't think it would be acceptable for many Canadians to have that high of a level of carbon tax to reach our emissions target. That's why I think other measures in combination with the carbon tax are probably necessary.
I'm not surprised to hear that ECCC officials indicated that 30% of the emissions reductions are due to the carbon tax.