> Your house is not necessarily heated with electricity.
But it will be anyway, that's a matter of a few decades now. If you're currently replacing your heating system, I should hope you're switching to electricity.
Though I'd say let's get a heat pump and save like 2/3rds of the energy compared to making the heat from scratch. Depending on the climate you might need some additional heating a few weeks per year, and then yeah sure let's do mining, but that's not a stable basis for a cryptocurrency's security.