But you have more steps in the artificial fuel cycle. You want to use it as electricity storage? You lose 30% in converting electricity to fuel, and 50% of what is left by converting it back, leaving 35% of the initial electricity to go back to the grid. You want to use it in cars? Fine, you save oil, which then can be used in power plants to produce electricity - but you get only 35% of what you needed to make the fuel, as the same factors apply.
You want to replace the oil? Compared to electric cars, you lose 30% in the conversion to fuel and more than 50% in the car, so that efficiency is even worse.In the short run, yes, in the long run, no. A large part of what consumers pay for electricity goes to maintenance of the grid and to taxes. Taxes are just a redistribution of money, not actual costs. You still need the grid with rooftop solar - even worse, you need it more than before because electricity production in a region gets more variable. If you reduce demand, the costs per kWh for those things will go up. Rooftop solar should be compared to power plants, otherwise you are cheating with the accounting.