well, I had read about plastics. Some new bacteria had mutated and are now
extracting energy from plastics.
As for the gas, it is apparent there is more gas than oil. But this idea can
be related to the more cumbersome way of transporting gas. It is also
dangerous of exploding. You said gas for some decades. We have also oil for
some decades. Perhaps not for more than 2 decades. But as the oil began
to look scarce and more expansive, we would start to consume gas or more
coal. Also we would began to build more atomic centrals.
The main problem I see is that money is pursuing a short term profit. The
great inversions are always a task for the government; like when the railways
or the atomic centrals of energy, or even many developments in computers,
programming, biology, aviation, etc. Many of the great inventions that are
now the property of multinationals were breed by government financing. But
now with the government in ruin, without barely any earning, I do not see
who is going to invest in the future.
If they get nervous this would end in a global war with the aim of holding
the last oil reserves. The civil war of Syria and Yemen can be understood
in the logic of oil getting exhausted.
When some climatic catastrophe, like a lower temperature, occurs, all empires
collapse. With lower temperature the SST plunges and the rains get scarce.
This is called a drought. The Roman empire collapsed for this reason. All
sort of hungry armed bandits went to Rome for it has a fame of having a lot
of food, and balmier weather. The bronze age empires collapsed for the same
reason. The old Kingdom of Egypt also collapsed at that time, 4250 years ago
for the might Nile had become a miserable brook.
Then, the exhaustion of oil is equivalent to Nile becoming dry for the whole
planet.
eri