The whole Ontario electrical sector has been hugely mis-managed by NDP, PC and Liberal governments. Even at current power rates, maintenance and upgrade budgets aren't adequate, let alone expansion, and certainly not new nuclear. The moratorium on offshore wind was exceptionally bad policy as was the half-assed privatization attempt.

The last greenfield nuke plant built in Canada was Darlington and it ended up way over budget (equivalent of $23B in today's money) and 5 years behind schedule. The Bruce refurbishments have been pretty successful, the Point Lepreau refurbishment, much less so. But new nuclear is a completely different ball of wax. With AECL being sold off to SNC by Harper, we don't have the domestic talent for new CANDUs anymore. The experience with AP1000s (V.C.Summer, Vogtle) and EPRs (Hinkley Point C, Flamanville, Olkiluoto, Taishan) has been really dismal.