Reducing Canada’s greenhouse gas (GHG) emissions is not rocket science. Our policies need to make climate-related pollution more expensive via carbon pricing or more restrictive via performance regulations. Governments may also give tax breaks and grants to households and industries to foster low-GHG choices.

But climate-policy experts know from decades of evidence that without carbon pricing or regulations to decarbonize our energy system, population and economic growth will cause GHG emissions to rise.

Our analysis of the party platforms for the April 28 election shows that GHG emissions would fall by 2035 under the Liberal approach – even with the removal of the unpopular but effective consumer carbon tax. They would rise under the Conservative plan to axe existing performance regulations along with the carbon tax.

The Conservatives argue that investing in clean technologies – nuclear energy, hydroelectricity, tidal power and carbon capture, utilization and storage – and removing red tape around developing these options will reduce emissions, although they have not outlined the details of these promises.

However, experts have long known that energy-supply subsidy programs alone do not reduce emissions in the end-use sectors of industry, buildings, and transport.

In addition, neither the Liberals nor the Conservatives have announced details of the impact on emissions of any policies they might enact to combat U.S. President Donald Trump’s trade war, such as short- or medium-term expansion of oil and gas production or building new pipelines. Therefore, these have only a modest effect in our analysis.

Decarbonization does not happen overnight

Transforming the stock of electricity plants, vehicles, home heating and industries occurs only gradually as government policies induce lower-carbon choices when people and firms naturally replace aging equipment and vehicles.

Gradual adoption of low-emission technologies has enabled Canada’s emissions to flatten over the last 20 years despite a 25-per-cent increase in the country’s population. But that general trend masks a few key developments.

One big source of emission reductions was the closure of all coal-fired power plants in Ontario from 2005-15, followed by the closure of coal plants in Alberta. Offsetting those, however, has been the steady growth of emissions from transportation, as well as from the oil and gas sector.

Since 2015, the carbon pricing and performance regulations implemented by the Trudeau Liberal government in sectors such as industry, electricity and transportation have started to significantly reduce per-capita GHG emissions.

Mark Carney has given us a sensible next step after the carbon tax. We need to take it.

From 2019: Emissions will rise under Conservative climate plan

What should be in a plain-speaking Conservative climate plan

Before we “axe the tax,” a quick lesson in history and physics

Independent analysis shows future Canadian emissions falling, even with Prime Minister Mark Carney’s elimination of the consumer carbon tax.

These federal policies are key to ensuring that the national decarbonization effort is cost-effective and co-ordinated. Yet, the Conservatives led by Piere Poilievre promise to remove all or most of them if they form the next government.

The differences in the approach of the two main federal political parties are significant.

(We focused our limited time for this analysis on the two parties that pollsters suggest have the greatest chance of forming a government after the election. In addition, we use identical forecasts from Statistics Canada for population and GDP growth – the “medium growth scenario” – for both parties. We also note that our 2030 forecast is similar to analyses from the Canadian Climate Institute.)

Forecasting Canada’s GHG emissions under Liberal policies

Several independent energy-economy modelling teams have produced estimates of the effect to 2030 and beyond of current federal Liberal policies. The Canadian Climate Institute assessed these studies and provided an estimate of their impact to 2030.

We have produced a similar estimate, with one caveat. We do not analyze the effect of various subsidies such as tax credits and grants because all political parties promise these and they have only a marginal effect on GHG emissions. We focus instead on the key regulatory and pricing policies because these are the most important for reducing GHG emissions. These include:

• The industrial output-based pricing system to reduce the intensity of industrial carbon emissions;
• regulations to reduce methane emissions from oil and gas production;
• clean-fuel regulations requiring declining intensity of emissions from carbons in fuel;
• the electric-vehicle availability standard requiring increased sales of zero-emission vehicles;
• clean-electricity regulations requiring declining intensity of emissions from the production of electricity.

For our simulation of these policies, we used the CIMS energy-economy model, which has for decades analyzed GHG policies at the behest of leaders across the political spectrum. Because it takes years for policies to influence GHG trajectories, we ran the CIMS model to 2035.

Canadian GHG emissions are expected to be approximately 680 megatonnes of carbon dioxide equivalent in 2025. Our simulation shows that Liberal policies would reduce this to about 600 megatonnes by 2035 especially if the Liberals strengthen their industrial output-based pricing system as the Canadian Climate Institute has proposed.

Thus, while our forecast suggests the Liberals are not on a trajectory to achieve their national 2030 GHG target of a 40- to 45-per-cent reduction below 2005 levels, their policies would at least drive significant emission reductions by 2035.

While most economists would prefer Canada to retain the carbon tax because this is likely the most economically efficient policy, it is still possible to significantly reduce GHG emissions thanks to the Liberals’ remaining regulatory policies.

Forecasting GHG emissions under promised Conservative policies

The federal Conservatives have promised for years to remove the consumer carbon tax. But given Carney’s move to kill it, it is no longer a factor in our simulations of both Liberal and Conservative climate approaches.

However, the Conservatives have promised to also remove key existing Liberal regulatory policies that would drive decarbonization in the absence of a consumer carbon tax.

Specifically, Poilievre has committed to removing the output-based pricing system, the clean fuel regulations, the electric-vehicle availability standard and the clean-electricity regulations. The potential emissions-reduction contribution of these regulations grows in importance in the absence of the consumer carbon tax.

Figure 1 shows our forecast that emissions would increase to approximately 720 megatonnes in 2035 from 680 megatonnes in 2025 if the Conservatives remove these policies and don’t replace them with something else.

Specifically, without the emission-reducing pressure of the output-based pricing system, emissions from industry and oil and gas production would grow by about 40 megatonnes relative to today.

Emissions from transportation would be higher with the elimination of the electric-vehicle availability standard and the clean-fuel regulations. Removal of these would also slow the adoption of zero-emission personal vehicles, except in B.C. and Quebec, which have their own provincial programs.

The elimination of the clean-fuel regulations would slow the adoption of biodiesel, hydrogen and other low-emission options in trucking, rail, shipping and air transportation.

By contrast, electricity emissions would not be significantly different under the existing Liberal government policies or the Conservative promises because the current version of the clean-electricity regulations has minimal effect during the 2025-35 period.

When governments first attempted GHG policies in the 1990s, they avoided carbon pricing and regulatory policies in the hope that encouraging voluntary actions, combined with incentives for technology innovation and early adoption, would be enough to reduce GHG emissions.

Considerable evidence has refuted this assumption. Yet the federal Conservatives under Poilievre still suggest that removing carbon pricing and key regulations will not lead to rising GHG emissions, even as populations and economies grow. The evidence suggests otherwise.

The authors thank Brad Griffin and Mark Jaccard for reviewer comments but the authors are solely responsible for all assumptions and analysis. Details on assumptions, data inputs, model methodology and modelling results are available on request.