A report late last year by the Independent Electricity System Operator found that the province could fully eliminate natural gas from the electricity system by 2050, starting with a moratorium in 2027, but it will require about $400 billion in capital spending and more generation including new, large-scale nuclear plants.
Decarbonizing the grid, in addition to new nuclear, will require more conservation efforts, more renewable energy sources and more energy storage, the report concluded.
The IESO said work should start now to assess the reliability of new and relatively untested technologies and fuels to replace natural gas, and to set up large, new generation sources such as nuclear plants and hydroelectric facilities.
The province has not committed to a natural gas moratorium or phase-out, or to building new nuclear facilities other than its small modular reactor plans, but it is now consulting on the prospect.
A document recently posted to the government's environmental registry asks for input on how best to engage the public and Indigenous communities on the planning and location of new generation and storage facilities.
Building new nuclear plants is "one pathway" toward a fully electrified system, Energy Minister Todd Smith said in an interview.
"It’s a possibility, for sure, and that’s why we’re looking for the feedback from Ontarians," he said. "We’re considering all of the next steps."
Environmental groups such as Environmental Defence oppose new nuclear builds, as well as the continued reliance on natural gas.
"Building new nuclear is absurd when we have safe and much cheaper alternatives such as wind and solar power."
The IESO has said the flexibility natural gas provides is needed to keep the system stable while new and relatively untested technologies are explored and new infrastructure gets built, but also as an electricity supply crunch looms.
The government consultation also asks whether "additional investment" should be made in clean energy in the short term in order to decrease reliance on natural gas, "even if this will increase costs to the electricity system and ratepayers."
But Smith indicated the government isn't keen on higher costs.
"We're not going to sacrifice reliability and affordability," he said. "We have to have a reliable and affordable system, otherwise we won’t have people moving to electrification."
The former Liberal government faced widespread anger over high hydro bills–highlighted often by the Progressive Conservatives, then in Opposition–driven up in part by long-term contracts at above-market rates with clean power producers secured to spur a green energy transition.
The current government consultation is open until May 14.