Solar power is cheaper than oil, but it doesn't work 24/7. If you can find a way to work with that, switching to solar is already financially incentivised. Even if you can't, we're already seeing whole countries and regions saturating at 100% solar electricity during daylight hours, significantly reducing oil usage. It doesn't matter what the oil sellers want, because it's a buyer's market for energy when the sun is out, and they're not going to throw extra money at oil companies just because.