In Alberta some of the extra charges vary based on usage, some are fixed. I don't seem to have found as good a retailer as ggenge (I'd love to know who he's with!) but the variable portion of my bill is $0.14/kwh plus a fixed portion (electricity is quoted as $0.08/kwh, but the other variable fees push it up to the $0.14)
However, because they don't net-meter, instead they meter bidrectionally, solar only recoups the $0.08 and not the variable portion of the rest of the bill unless you manage to use what you produce. Unfortunately for a Tesla owner who works outside of the house, most usage is overnight, and most production is during the day, so you'd need battery storage to not be shafted on the bill.