Ontario produces a majority of its electric power from nuclear (https://en.wikipedia.org/wiki/Nuclear_power_in_Canada) and manages to sell it at competitive rates (https://www.oeb.ca/consumer-information-and-protection/elect...) similar to those in Alberta (https://ucahelps.alberta.ca/your-utilities/rates/historic-ra...) where electricity comes mainly from natural gas after a recent transition from mostly coal. A 2021 report cited at https://www.cns-snc.ca/learn-nuclear/basics-of-nuclear/how-m... finds that nuclear power in Ontario was more cost effective than everything else except hydroelectric power (granted, solar has become much cheaper in just the last few years). And this is in spite of multiple reactor shutdowns.

Yes, running a nuclear power plant is pretty cheap, if you ignore the cost of building and decommissioning it.