Over the last two decades, Ontario has taken great strides in eliminating carbon emissions from its electricity grid by removing the primary source of carbon emissions: coal-fired generation. In 2005, Ontario’s coal plants alone were responsible for 17% of the province’s emissions. Today, those coal plants are completely shut down and the only source of emissions left on Ontario’s electricity grid is the 6% of power generated by natural gas.
Ontario was able to end its dependence on coal by relying heavily on nuclear power. Immediately after the final coal plant closed, nuclear power provided 60% of Ontario’s electricity and electricity sector emissions reached an all-time low. That’s because nuclear power, over its entire lifecycle, generates just 1.6% of the emissions that coal does and 2.7% of natural gas’s emissions.
In recent years, nuclear power has provided closer to 50% of Ontario’s electricity. This reduction was necessary so that the reactors at Bruce and Darlington Nuclear Generating Stations (NGS) could be refurbished one by one as part of extending their operations beyond 2050. The Pickering NGS is slated to be decommissioned in 2025-26 but now Ontario Power Generation is considering whether to refurbish four of Pickering’s six reactors. If Pickering is not refurbished, nuclear power’s share of the electricity supply mix will fall to just 35%.
The issue with a reduction in nuclear power is that Ontario still needs all of the power nuclear provides. If nuclear power is not available, Ontario has no choice but to burn carbon-intensive natural gas. Consequently, Ontario’s carbon emissions have already begun to increase and they are slated to increase much further over the next 20 years.