It is expensive (the most expensive in North America *) because it is low in fossil fuel generation AND uses a lot of renewables with variable production.

The only way to keep the system stable is to rely on fossil fuel generation outside the jurisdiction to offset the peaks and troughs that happen on short time scales.

Ontario actually pays the bordering states to take away excess energy, and they can do it because their gas fired generation can act in seconds to balance supply and demand.

The power EXPORT from the windmills costs the ratepayers in the province over $1B a year…

Similarly, many of the hydro projects rely on seasonal foreign demand. For example BC produces a lot of extra hydro in summer season, and there is air conditioning demand in California during those months. Its not as if the province can hold that water and use it for heating homes during winter.

(* because of unreliable supplies, large consumers like industry can’t actually operate in the province because they cannot get reliable contracts… This is about 1/2 million jobs. This is a big part of how Ontario became a have-not province, actually. I had multiple clients from Ontario’s generating sector who told me that they “did not want” to enter power contracts with penalties around outages, so if a car plant loses power they can lose millions per hour, and the power companies didn’t want to commit to anything. All things equal, big factories can move to Buffalo NY and pay half the price for Ontario energy… )

Basically, it’s expensive because of the costs of remote jurisdiction dependencies and the lack of true self sufficiency.