They've already started: World Bank Urges Global Action to Save Oceans They will head off using any of Earth's sun absorbing ocean surface to grow genetically engineered algae. The water, real estate, and sunshine are unlimited and free for the taking. Petroleum could be entirely replaced using less than 2% of the ocean surface, but the lefties will have none of it. They think they've got us cornered and are not about to let us go free.
The algae breakthrough will come from USA military research spending, not from Barky's repeat of Carter's Aquatic Species Program. When the breakthrough happens is largely dependent on when we get serious about it. It will probably occur sometime within the next 50 years, which means we've got less than 50 years to pump all the oil out of the ground before it is completely worthless. Drill here, drill now, because it's going out of style!
I don't know anything about it but I do know living things need more then sunshine to grow. If you are taking millions of gallons of oil out of the ocean every year(via algae) something is being taken out of the ocean to make it that and will have to be replaced.
What inputs (besides sunlight) will this process use?