The growth looks exponential (and technically probably is, just not in the normal sense of that phrase).
Like any physical process, it’s likely to be limited and follow something more like a Logistic function, which looks exponential at the start but ceases to follow that curve forever (which matters for making multi-decade projections).
Citing "primary" energy is a great way to be off by several factors on any estimate.
Electrification results in 2x-5x less energy use for nearly every large energy application. Take, for example, heat humps. Fossil fuels are only something like 95% efficient, whereas heat pumps product 200%-500% efficient. Same goes for EVs over fuel engines, etc.
Old sources of energy get replaced all the time. Not sure why you think that's not the case...
Primary energy usage is an awful metric. When replacing ICE cars with EVs we do not need to replace the energy used with a 1:1 ratio. The ICE is 20-35% efficient, and this is spread across the supply chain for both the fuel and the car itself.
See this amazing flow chart on useful vs. rejected energy:
Sure, look at that chart. According to that chart, we'll burn coal forever. Now, consult reality for a moment, or take a look around. Coal is finite, a resources stored away over a tremendous period of time, much of it burned in about a century. So your "always" is at best temporarily true, and thus worthless, it can't actually have predictive power.
Although you insist that new sources "always come on top" you're either just observing that the chart was designed this way (facile) or you didn't look at the actual data closely.
In 2014 there was more "traditional biomass" (ie people burn stuff) than today. Since this practice is extremely inefficient it makes sense to see it phased out, cooking food over a literal log fire is simple but that's the only upside.
Also Solar looks like about 2.5% to me. How is that "negligible" ? Is the population of Bangladesh "negligible"? That's about 2.5% of the world's population.
>Coal is finite, a resources stored away over a tremendous period of time, much of it burned in about a century
Sure, it's finite, but we will run out of oil and natural gas much faster than of coal. There are centuries worth of known economically viable coal reserves. Even more, if we count low-quality lignite and peat reserves.
Do those 'centuries' include the large increases in power demands across the world, ( as the wider world develops ) and the requirement to replace the missing oil and gas when they run out?
People would choke to death before we could use that much coal, so I doubt that will matter. It’s effectively infinite: We have access to more than we will ever want to use.
> Although you insist that new sources "always come on top" you're either just observing that the chart was designed this way (facile) or you didn't look at the actual data closely.
I mean that new energy sources came in addition to existing ones. We consume as much wood as we ever did. Coal didn't reduce wood usage. Oil didn't reduce coal and so on...
Nuclear did remove almost completely fossil fuels from the French electricity grid. Only example I know of of a grid that succeeded in getting rid of almost all fossil fuels. (transport and heating keep using a lot of fossils however)
https://ourworldindata.org/global-energy-200-years
1. Share of solar is negligible 2. New sources of energy have always come on top of existing sources, never replaced them