Fossil fuels are running out. Civilization depends on energy. How do we make this not go badly?
Most alternatives have issues:
Each will have their place, but Solar stands out as the likely core energy source because:
"Super awkward photoshoot when they made this diagram because solar is just a weird size compared to the others. And if the chart isn’t already silly enough, note that those are spheres—if they were two-dimensional circles, wind would have the diameter of a marble, coal would be the size of a bowling ball, and solar would be the size of a small house." - The Deal With Solar, WaitButWhy.
The raw materials for solar panels are abundant, and we're not going to run out of space. It would require a great deal of resources to panel roofs and create the vast solar farms required to generate enough raw energy to power everything we want from solar, but fundamentally we have the technology.
The hard bit is intermittency. Currently a power grid mostly supplied by solar would have a massive overabundance of electrical power in the day and not enough at night. Germany has this problem. If solar is to step up in a big way, we need grid scale storage.
https://www.sciencedaily.com/releases/2013/03/130308111310.htm