No law of economics… are you that sure? France is the poster boy of nuclear energy and has been pushing very hard for electric domestic heating over the years and yet it simply has almost never made any sense for homeowners to opt for electric heating rather than natural gas. Indeed, though French electricity prices have always been probably the lowest in Western Europe, it still always comes up some 50% more expensive than natural gas. The only major reason property owners switch to electric is that it's cheaper to install, so using in it in rentals shifts higher energy prices onto tenants while property owners benefit from lower investment costs. Clearly, not building more power plants isn't really what went wrong here.