You know the world is not really at risk of running out of oil ever; as oil starts running out it will become more and more expensive and more research will flow into other technologies. Already, gas is an economically feasible alternative. Basically, there is a 0% chance of coming to a moment where people are like "wait, oil, gas and coal are out, what now?" and prices suddenly spike heavily or something. That's not going to happen.
Whether it be solar, wind, hydro energy or something else, some renewable technology will arise and as it is perfected it will probably become a lot cheaper than oil is now.
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Do not pray for easier lives. Pray to be stronger men. - John F. Kennedy